[2346] | 1 | /* -*- C++ -*- |
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| 2 | * |
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| 3 | * This file is a part of LEMON, a generic C++ optimization library |
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| 4 | * |
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[2391] | 5 | * Copyright (C) 2003-2007 |
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[2346] | 6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
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| 7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
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| 8 | * |
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| 9 | * Permission to use, modify and distribute this software is granted |
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| 10 | * provided that this copyright notice appears in all copies. For |
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| 11 | * precise terms see the accompanying LICENSE file. |
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| 12 | * |
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| 13 | * This software is provided "AS IS" with no warranty of any kind, |
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| 14 | * express or implied, and with no claim as to its suitability for any |
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| 15 | * purpose. |
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| 16 | * |
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| 17 | */ |
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| 18 | |
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| 19 | #ifndef LEMON_ELEVATOR_H |
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| 20 | #define LEMON_ELEVATOR_H |
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| 21 | |
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| 22 | ///\ingroup auxdat |
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| 23 | ///\file |
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| 24 | ///\brief Elevator class |
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| 25 | /// |
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| 26 | ///Elevator class implements an efficient data structure |
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| 27 | ///for labeling items in push-relabel type algorithms. |
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| 28 | /// |
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| 29 | |
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| 30 | #include <test/test_tools.h> |
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| 31 | namespace lemon { |
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| 32 | |
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[2347] | 33 | ///Class for handling "labels" in push-relabel type algorithms. |
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[2346] | 34 | |
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[2347] | 35 | ///A class for handling "labels" in push-relabel type algorithms. |
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[2346] | 36 | /// |
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| 37 | ///\ingroup auxdat |
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[2352] | 38 | ///Using this class you can assign "labels" (nonnegative integer numbers) |
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[2346] | 39 | ///to the edges or nodes of a graph, manipulate and query them through |
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| 40 | ///operations typically arising in "push-relabel" type algorithms. |
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| 41 | /// |
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| 42 | ///Each item is either \em active or not, and you can also choose a |
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| 43 | ///highest level active item. |
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| 44 | /// |
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[2512] | 45 | ///\sa LinkedElevator |
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| 46 | /// |
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[2346] | 47 | ///\param Graph the underlying graph type |
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| 48 | ///\param Item Type of the items the data is assigned to (Graph::Node, |
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| 49 | ///Graph::Edge, Graph::UEdge) |
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| 50 | template<class Graph, class Item> |
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| 51 | class Elevator |
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| 52 | { |
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[2512] | 53 | private: |
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| 54 | |
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| 55 | typedef Item Key; |
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| 56 | typedef int Value; |
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| 57 | |
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[2346] | 58 | typedef typename std::vector<Item>::iterator Vit; |
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[2512] | 59 | typedef typename ItemSetTraits<Graph,Item>::template Map<Vit>::Type VitMap; |
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| 60 | typedef typename ItemSetTraits<Graph,Item>::template Map<int>::Type IntMap; |
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[2346] | 61 | |
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| 62 | const Graph &_g; |
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| 63 | int _max_level; |
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| 64 | int _item_num; |
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| 65 | VitMap _where; |
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| 66 | IntMap _level; |
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| 67 | std::vector<Item> _items; |
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| 68 | std::vector<Vit> _first; |
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| 69 | std::vector<Vit> _last_active; |
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| 70 | |
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| 71 | int _highest_active; |
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| 72 | |
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| 73 | void copy(Item i, Vit p) |
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| 74 | { |
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| 75 | _where[*p=i]=p; |
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| 76 | } |
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| 77 | void copy(Vit s, Vit p) |
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| 78 | { |
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| 79 | if(s!=p) |
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| 80 | { |
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| 81 | Item i=*s; |
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| 82 | *p=i; |
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| 83 | _where[i]=p; |
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| 84 | } |
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| 85 | } |
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| 86 | void swap(Vit i, Vit j) |
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| 87 | { |
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| 88 | Item ti=*i; |
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| 89 | Vit ct = _where[ti]; |
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| 90 | _where[ti]=_where[*i=*j]; |
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| 91 | _where[*j]=ct; |
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| 92 | *j=ti; |
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| 93 | } |
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| 94 | |
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| 95 | public: |
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[2512] | 96 | |
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[2346] | 97 | ///Constructor with given maximum level. |
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| 98 | |
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| 99 | ///Constructor with given maximum level. |
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| 100 | /// |
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| 101 | ///\param g The underlying graph |
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| 102 | ///\param max_level Set the range of the possible labels to |
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| 103 | ///[0...\c max_level] |
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| 104 | Elevator(const Graph &g,int max_level) : |
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| 105 | _g(g), |
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| 106 | _max_level(max_level), |
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| 107 | _item_num(_max_level), |
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| 108 | _where(g), |
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| 109 | _level(g,0), |
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| 110 | _items(_max_level), |
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| 111 | _first(_max_level+2), |
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| 112 | _last_active(_max_level+2), |
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| 113 | _highest_active(-1) {} |
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| 114 | ///Constructor. |
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| 115 | |
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| 116 | ///Constructor. |
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| 117 | /// |
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| 118 | ///\param g The underlying graph |
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| 119 | ///The range of the possible labels is [0...\c max_level], |
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| 120 | ///where \c max_level is equal to the number of labeled items in the graph. |
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| 121 | Elevator(const Graph &g) : |
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| 122 | _g(g), |
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| 123 | _max_level(countItems<Graph, Item>(g)), |
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| 124 | _item_num(_max_level), |
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| 125 | _where(g), |
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| 126 | _level(g,0), |
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| 127 | _items(_max_level), |
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| 128 | _first(_max_level+2), |
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| 129 | _last_active(_max_level+2), |
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| 130 | _highest_active(-1) |
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| 131 | { |
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| 132 | } |
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[2512] | 133 | |
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[2346] | 134 | ///Activate item \c i. |
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[2373] | 135 | |
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| 136 | ///Activate item \c i. |
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| 137 | ///\pre Item \c i shouldn't be active before. |
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[2346] | 138 | void activate(Item i) |
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| 139 | { |
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| 140 | const int l=_level[i]; |
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| 141 | swap(_where[i],++_last_active[l]); |
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| 142 | if(l>_highest_active) _highest_active=l; |
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| 143 | } |
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| 144 | |
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| 145 | ///Deactivate item \c i. |
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[2373] | 146 | |
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| 147 | ///Deactivate item \c i. |
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| 148 | ///\pre Item \c i must be active before. |
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[2346] | 149 | void deactivate(Item i) |
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| 150 | { |
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| 151 | swap(_where[i],_last_active[_level[i]]--); |
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| 152 | while(_highest_active>=0 && |
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| 153 | _last_active[_highest_active]<_first[_highest_active]) |
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| 154 | _highest_active--; |
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| 155 | } |
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| 156 | |
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| 157 | ///Query whether item \c i is active |
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| 158 | bool active(Item i) const { return _where[i]<=_last_active[_level[i]]; } |
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| 159 | |
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| 160 | ///Return the level of item \c i. |
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| 161 | int operator[](Item i) const { return _level[i]; } |
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| 162 | |
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| 163 | ///Return the number of items on level \c l. |
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[2348] | 164 | int onLevel(int l) const |
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[2346] | 165 | { |
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| 166 | return _first[l+1]-_first[l]; |
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| 167 | } |
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[2512] | 168 | ///Return true if the level is empty. |
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| 169 | bool emptyLevel(int l) const |
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| 170 | { |
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| 171 | return _first[l+1]-_first[l]==0; |
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| 172 | } |
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[2348] | 173 | ///Return the number of items above level \c l. |
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| 174 | int aboveLevel(int l) const |
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| 175 | { |
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| 176 | return _first[_max_level+1]-_first[l+1]; |
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| 177 | } |
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[2346] | 178 | ///Return the number of active items on level \c l. |
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[2348] | 179 | int activesOnLevel(int l) const |
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[2346] | 180 | { |
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| 181 | return _last_active[l]-_first[l]+1; |
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| 182 | } |
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[2512] | 183 | ///Return true if there is not active item on level \c l. |
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| 184 | bool activeFree(int l) const |
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| 185 | { |
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| 186 | return _last_active[l]<_first[l]; |
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| 187 | } |
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[2346] | 188 | ///Return the maximum allowed level. |
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| 189 | int maxLevel() const |
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| 190 | { |
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| 191 | return _max_level; |
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| 192 | } |
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| 193 | |
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| 194 | ///\name Highest Active Item |
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| 195 | ///Functions for working with the highest level |
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| 196 | ///active item. |
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| 197 | |
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| 198 | ///@{ |
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| 199 | |
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| 200 | ///Return a highest level active item. |
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| 201 | |
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| 202 | ///Return a highest level active item. |
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| 203 | /// |
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| 204 | ///\return the highest level active item or INVALID if there is no active |
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| 205 | ///item. |
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| 206 | Item highestActive() const |
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| 207 | { |
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| 208 | return _highest_active>=0?*_last_active[_highest_active]:INVALID; |
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| 209 | } |
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| 210 | |
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| 211 | ///Return a highest active level. |
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| 212 | |
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| 213 | ///Return a highest active level. |
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| 214 | /// |
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| 215 | ///\return the level of the highest active item or -1 if there is no active |
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| 216 | ///item. |
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[2349] | 217 | int highestActiveLevel() const |
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[2346] | 218 | { |
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| 219 | return _highest_active; |
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| 220 | } |
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| 221 | |
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| 222 | ///Lift the highest active item by one. |
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| 223 | |
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| 224 | ///Lift the item returned by highestActive() by one. |
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| 225 | /// |
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| 226 | void liftHighestActive() |
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| 227 | { |
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| 228 | ++_level[*_last_active[_highest_active]]; |
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| 229 | swap(_last_active[_highest_active]--,_last_active[_highest_active+1]); |
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| 230 | --_first[++_highest_active]; |
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| 231 | } |
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| 232 | |
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| 233 | ///Lift the highest active item. |
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| 234 | |
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| 235 | ///Lift the item returned by highestActive() to level \c new_level. |
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| 236 | /// |
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[2348] | 237 | ///\warning \c new_level must be strictly higher |
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| 238 | ///than the current level. |
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[2346] | 239 | /// |
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[2512] | 240 | void liftHighestActive(int new_level) |
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[2346] | 241 | { |
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| 242 | const Item li = *_last_active[_highest_active]; |
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| 243 | |
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| 244 | copy(--_first[_highest_active+1],_last_active[_highest_active]--); |
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| 245 | for(int l=_highest_active+1;l<new_level;l++) |
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| 246 | { |
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| 247 | copy(--_first[l+1],_first[l]); |
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| 248 | --_last_active[l]; |
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| 249 | } |
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| 250 | copy(li,_first[new_level]); |
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| 251 | _level[li]=new_level; |
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[2348] | 252 | _highest_active=new_level; |
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[2346] | 253 | } |
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[2512] | 254 | |
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| 255 | ///Lift the highest active item. |
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| 256 | |
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| 257 | ///Lift the item returned by highestActive() to the top level and |
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| 258 | ///deactivates it. |
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| 259 | /// |
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| 260 | ///\warning \c new_level must be strictly higher |
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| 261 | ///than the current level. |
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| 262 | /// |
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| 263 | void liftHighestActiveToTop() |
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| 264 | { |
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| 265 | const Item li = *_last_active[_highest_active]; |
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| 266 | |
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| 267 | copy(--_first[_highest_active+1],_last_active[_highest_active]--); |
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| 268 | for(int l=_highest_active+1;l<_max_level;l++) |
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| 269 | { |
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| 270 | copy(--_first[l+1],_first[l]); |
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| 271 | --_last_active[l]; |
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| 272 | } |
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| 273 | copy(li,_first[_max_level]); |
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| 274 | --_last_active[_max_level]; |
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| 275 | _level[li]=_max_level; |
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| 276 | |
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| 277 | while(_highest_active>=0 && |
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| 278 | _last_active[_highest_active]<_first[_highest_active]) |
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| 279 | _highest_active--; |
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| 280 | } |
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[2346] | 281 | |
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| 282 | ///@} |
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| 283 | |
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[2512] | 284 | ///\name Active Item on Certain Level |
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| 285 | ///Functions for working with the active items. |
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| 286 | |
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| 287 | ///@{ |
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| 288 | |
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| 289 | ///Returns an active item on level \c l. |
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| 290 | |
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| 291 | ///Returns an active item on level \c l. |
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| 292 | /// |
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| 293 | ///Returns an active item on level \c l or \ref INVALID if there is no such |
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| 294 | ///an item. (\c l must be from the range [0...\c max_level]. |
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| 295 | Item activeOn(int l) const |
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| 296 | { |
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| 297 | return _last_active[l]>=_first[l]?*_last_active[l]:INVALID; |
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| 298 | } |
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| 299 | |
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| 300 | ///Lifts the active item returned by \c activeOn() member function. |
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| 301 | |
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| 302 | ///Lifts the active item returned by \c activeOn() member function |
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| 303 | ///by one. |
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| 304 | Item liftActiveOn(int level) |
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| 305 | { |
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| 306 | ++_level[*_last_active[level]]; |
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| 307 | swap(_last_active[level]--, --_first[level+1]); |
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| 308 | if (level+1>_highest_active) ++_highest_active; |
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| 309 | } |
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| 310 | |
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| 311 | ///Lifts the active item returned by \c activeOn() member function. |
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| 312 | |
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| 313 | ///Lifts the active item returned by \c activeOn() member function |
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| 314 | ///to the given level. |
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| 315 | void liftActiveOn(int level, int new_level) |
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| 316 | { |
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| 317 | const Item ai = *_last_active[level]; |
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| 318 | |
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| 319 | copy(--_first[level+1], _last_active[level]--); |
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| 320 | for(int l=level+1;l<new_level;l++) |
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| 321 | { |
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| 322 | copy(_last_active[l],_first[l]); |
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| 323 | copy(--_first[l+1], _last_active[l]--); |
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| 324 | } |
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| 325 | copy(ai,_first[new_level]); |
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| 326 | _level[ai]=new_level; |
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| 327 | if (new_level>_highest_active) _highest_active=new_level; |
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| 328 | } |
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| 329 | |
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| 330 | ///Lifts the active item returned by \c activeOn() member function. |
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| 331 | |
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| 332 | ///Lifts the active item returned by \c activeOn() member function |
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| 333 | ///to the top level. |
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| 334 | void liftActiveToTop(int level) |
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| 335 | { |
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| 336 | const Item ai = *_last_active[level]; |
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| 337 | |
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| 338 | copy(--_first[level+1],_last_active[level]--); |
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| 339 | for(int l=level+1;l<_max_level;l++) |
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| 340 | { |
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| 341 | copy(_last_active[l],_first[l]); |
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| 342 | copy(--_first[l+1], _last_active[l]--); |
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| 343 | } |
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| 344 | copy(ai,_first[_max_level]); |
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| 345 | --_last_active[_max_level]; |
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| 346 | _level[ai]=_max_level; |
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| 347 | |
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| 348 | if (_highest_active==level) { |
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| 349 | while(_highest_active>=0 && |
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| 350 | _last_active[_highest_active]<_first[_highest_active]) |
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| 351 | _highest_active--; |
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| 352 | } |
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| 353 | } |
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| 354 | |
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| 355 | ///@} |
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| 356 | |
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[2348] | 357 | ///Lift an active item to a higher level. |
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| 358 | |
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| 359 | ///Lift an active item to a higher level. |
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[2350] | 360 | ///\param i The item to be lifted. It must be active. |
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| 361 | ///\param new_level The new level of \c i. It must be strictly higher |
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[2348] | 362 | ///than the current level. |
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| 363 | /// |
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[2512] | 364 | void lift(Item i, int new_level) |
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[2348] | 365 | { |
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| 366 | const int lo = _level[i]; |
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| 367 | const Vit w = _where[i]; |
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| 368 | |
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| 369 | copy(_last_active[lo],w); |
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| 370 | copy(--_first[lo+1],_last_active[lo]--); |
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| 371 | for(int l=lo+1;l<new_level;l++) |
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| 372 | { |
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| 373 | copy(_last_active[l],_first[l]); |
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| 374 | copy(--_first[l+1],_last_active[l]--); |
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| 375 | } |
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| 376 | copy(i,_first[new_level]); |
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| 377 | _level[i]=new_level; |
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| 378 | if(new_level>_highest_active) _highest_active=new_level; |
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| 379 | } |
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| 380 | |
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| 381 | ///Lift all nodes on and above a level to the top (and deactivate them). |
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| 382 | |
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[2512] | 383 | ///This function lifts all nodes on and above level \c l to \c |
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| 384 | ///maxLevel(), and also deactivates them. |
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[2348] | 385 | void liftToTop(int l) |
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| 386 | { |
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| 387 | const Vit f=_first[l]; |
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| 388 | const Vit tl=_first[_max_level]; |
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| 389 | for(Vit i=f;i!=tl;++i) |
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| 390 | _level[*i]=_max_level; |
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| 391 | for(int i=l;i<=_max_level;i++) |
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| 392 | { |
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| 393 | _first[i]=f; |
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| 394 | _last_active[i]=f-1; |
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| 395 | } |
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| 396 | for(_highest_active=l-1; |
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| 397 | _highest_active>=0 && |
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| 398 | _last_active[_highest_active]<_first[_highest_active]; |
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| 399 | _highest_active--) ; |
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| 400 | } |
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| 401 | |
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[2346] | 402 | private: |
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| 403 | int _init_lev; |
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| 404 | Vit _init_num; |
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| 405 | |
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| 406 | public: |
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| 407 | |
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| 408 | ///\name Initialization |
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| 409 | ///Using this function you can initialize the levels of the item. |
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| 410 | ///\n |
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| 411 | ///This initializatios is started with calling \c initStart(). |
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| 412 | ///Then the |
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| 413 | ///items should be listed levels by levels statring with the lowest one |
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| 414 | ///(with level 0). This is done by using \c initAddItem() |
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| 415 | ///and \c initNewLevel(). Finally \c initFinish() must be called. |
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[2348] | 416 | ///The items not listed will be put on the highest level. |
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[2346] | 417 | ///@{ |
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| 418 | |
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[2348] | 419 | ///Start the initialization process. |
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[2346] | 420 | |
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| 421 | void initStart() |
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| 422 | { |
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| 423 | _init_lev=0; |
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| 424 | _init_num=_items.begin(); |
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| 425 | _first[0]=_items.begin(); |
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| 426 | _last_active[0]=_items.begin()-1; |
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| 427 | Vit n=_items.begin(); |
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| 428 | for(typename ItemSetTraits<Graph,Item>::ItemIt i(_g);i!=INVALID;++i) |
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| 429 | { |
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| 430 | *n=i; |
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| 431 | _where[i]=n; |
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| 432 | _level[i]=_max_level; |
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| 433 | ++n; |
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| 434 | } |
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| 435 | } |
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| 436 | |
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| 437 | ///Add an item to the current level. |
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| 438 | |
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| 439 | void initAddItem(Item i) |
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| 440 | { |
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| 441 | swap(_where[i],_init_num); |
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| 442 | _level[i]=_init_lev; |
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| 443 | ++_init_num; |
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| 444 | } |
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| 445 | |
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| 446 | ///Start a new level. |
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| 447 | |
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| 448 | ///Start a new level. |
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| 449 | ///It shouldn't be used before the items on level 0 are listed. |
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| 450 | void initNewLevel() |
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| 451 | { |
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| 452 | _init_lev++; |
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| 453 | _first[_init_lev]=_init_num; |
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| 454 | _last_active[_init_lev]=_init_num-1; |
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| 455 | } |
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| 456 | |
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[2348] | 457 | ///Finalize the initialization process. |
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[2346] | 458 | |
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| 459 | void initFinish() |
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| 460 | { |
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| 461 | for(_init_lev++;_init_lev<=_max_level;_init_lev++) |
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| 462 | { |
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| 463 | _first[_init_lev]=_init_num; |
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| 464 | _last_active[_init_lev]=_init_num-1; |
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| 465 | } |
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| 466 | _first[_max_level+1]=_items.begin()+_item_num; |
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| 467 | _last_active[_max_level+1]=_items.begin()+_item_num-1; |
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[2512] | 468 | _highest_active = -1; |
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[2346] | 469 | } |
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| 470 | |
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| 471 | ///@} |
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| 472 | |
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| 473 | }; |
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| 474 | |
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[2512] | 475 | ///Class for handling "labels" in push-relabel type algorithms. |
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| 476 | |
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| 477 | ///A class for handling "labels" in push-relabel type algorithms. |
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| 478 | /// |
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| 479 | ///\ingroup auxdat |
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| 480 | ///Using this class you can assign "labels" (nonnegative integer numbers) |
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| 481 | ///to the edges or nodes of a graph, manipulate and query them through |
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| 482 | ///operations typically arising in "push-relabel" type algorithms. |
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| 483 | /// |
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| 484 | ///Each item is either \em active or not, and you can also choose a |
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| 485 | ///highest level active item. |
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| 486 | /// |
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| 487 | ///\sa Elevator |
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| 488 | /// |
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| 489 | ///\param Graph the underlying graph type |
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| 490 | ///\param Item Type of the items the data is assigned to (Graph::Node, |
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| 491 | ///Graph::Edge, Graph::UEdge) |
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| 492 | template <class Graph, class Item> |
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| 493 | class LinkedElevator { |
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| 494 | private: |
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| 495 | |
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| 496 | typedef Item Key; |
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| 497 | typedef int Value; |
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| 498 | |
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| 499 | typedef typename ItemSetTraits<Graph,Item>:: |
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| 500 | template Map<Item>::Type ItemMap; |
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| 501 | typedef typename ItemSetTraits<Graph,Item>:: |
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| 502 | template Map<int>::Type IntMap; |
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| 503 | typedef typename ItemSetTraits<Graph,Item>:: |
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| 504 | template Map<bool>::Type BoolMap; |
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| 505 | |
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| 506 | const Graph &_graph; |
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| 507 | int _max_level; |
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| 508 | int _item_num; |
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| 509 | std::vector<Item> _first, _last; |
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| 510 | ItemMap _prev, _next; |
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| 511 | int _highest_active; |
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| 512 | IntMap _level; |
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| 513 | BoolMap _active; |
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| 514 | |
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| 515 | public: |
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| 516 | ///Constructor with given maximum level. |
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| 517 | |
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| 518 | ///Constructor with given maximum level. |
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| 519 | /// |
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| 520 | ///\param g The underlying graph |
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| 521 | ///\param max_level Set the range of the possible labels to |
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| 522 | ///[0...\c max_level] |
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| 523 | LinkedElevator(const Graph& graph, int max_level) |
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| 524 | : _graph(graph), _max_level(max_level), _item_num(_max_level), |
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| 525 | _first(_max_level + 1), _last(_max_level + 1), |
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| 526 | _prev(graph), _next(graph), |
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| 527 | _highest_active(-1), _level(graph), _active(graph) {} |
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| 528 | |
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| 529 | ///Constructor. |
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| 530 | |
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| 531 | ///Constructor. |
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| 532 | /// |
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| 533 | ///\param g The underlying graph |
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| 534 | ///The range of the possible labels is [0...\c max_level], |
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| 535 | ///where \c max_level is equal to the number of labeled items in the graph. |
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| 536 | LinkedElevator(const Graph& graph) |
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| 537 | : _graph(graph), _max_level(countItems<Graph, Item>(graph)), |
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| 538 | _item_num(_max_level), |
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| 539 | _first(_max_level + 1), _last(_max_level + 1), |
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| 540 | _prev(graph, INVALID), _next(graph, INVALID), |
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| 541 | _highest_active(-1), _level(graph), _active(graph) {} |
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| 542 | |
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| 543 | |
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| 544 | ///Activate item \c i. |
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| 545 | |
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| 546 | ///Activate item \c i. |
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| 547 | ///\pre Item \c i shouldn't be active before. |
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| 548 | void activate(Item i) { |
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| 549 | _active.set(i, true); |
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| 550 | |
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| 551 | int level = _level[i]; |
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| 552 | if (level > _highest_active) { |
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| 553 | _highest_active = level; |
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| 554 | } |
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| 555 | |
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| 556 | if (_prev[i] == INVALID || _active[_prev[i]]) return; |
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| 557 | //unlace |
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| 558 | _next.set(_prev[i], _next[i]); |
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| 559 | if (_next[i] != INVALID) { |
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| 560 | _prev.set(_next[i], _prev[i]); |
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| 561 | } else { |
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| 562 | _last[level] = _prev[i]; |
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| 563 | } |
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| 564 | //lace |
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| 565 | _next.set(i, _first[level]); |
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| 566 | _prev.set(_first[level], i); |
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| 567 | _prev.set(i, INVALID); |
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| 568 | _first[level] = i; |
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| 569 | |
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| 570 | } |
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| 571 | |
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| 572 | ///Deactivate item \c i. |
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| 573 | |
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| 574 | ///Deactivate item \c i. |
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| 575 | ///\pre Item \c i must be active before. |
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| 576 | void deactivate(Item i) { |
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| 577 | _active.set(i, false); |
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| 578 | int level = _level[i]; |
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| 579 | |
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| 580 | if (_next[i] == INVALID || !_active[_next[i]]) |
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| 581 | goto find_highest_level; |
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| 582 | |
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| 583 | //unlace |
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| 584 | _prev.set(_next[i], _prev[i]); |
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| 585 | if (_prev[i] != INVALID) { |
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| 586 | _next.set(_prev[i], _next[i]); |
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| 587 | } else { |
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| 588 | _first[_level[i]] = _next[i]; |
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| 589 | } |
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| 590 | //lace |
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| 591 | _prev.set(i, _last[level]); |
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| 592 | _next.set(_last[level], i); |
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| 593 | _next.set(i, INVALID); |
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| 594 | _last[level] = i; |
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| 595 | |
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| 596 | find_highest_level: |
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| 597 | if (level == _highest_active) { |
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| 598 | while (_highest_active >= 0 && activeFree(_highest_active)) |
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| 599 | --_highest_active; |
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| 600 | } |
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| 601 | } |
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| 602 | |
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| 603 | ///Query whether item \c i is active |
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| 604 | bool active(Item i) const { return _active[i]; } |
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| 605 | |
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| 606 | ///Return the level of item \c i. |
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| 607 | int operator[](Item i) const { return _level[i]; } |
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| 608 | |
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| 609 | ///Return the number of items on level \c l. |
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| 610 | int onLevel(int l) const { |
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| 611 | int num = 0; |
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| 612 | Item n = _first[l]; |
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| 613 | while (n != INVALID) { |
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| 614 | ++num; |
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| 615 | n = _next[n]; |
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| 616 | } |
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| 617 | return num; |
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| 618 | } |
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| 619 | |
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| 620 | ///Return true if the level is empty. |
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| 621 | bool emptyLevel(int l) const { |
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| 622 | return _first[l] == INVALID; |
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| 623 | } |
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| 624 | |
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| 625 | ///Return the number of items above level \c l. |
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| 626 | int aboveLevel(int l) const { |
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| 627 | int num = 0; |
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| 628 | for (int level = l + 1; level < _max_level; ++level) |
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| 629 | num += onLevel(level); |
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| 630 | return num; |
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| 631 | } |
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| 632 | |
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| 633 | ///Return the number of active items on level \c l. |
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| 634 | int activesOnLevel(int l) const { |
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| 635 | int num = 0; |
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| 636 | Item n = _first[l]; |
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| 637 | while (n != INVALID && _active[n]) { |
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| 638 | ++num; |
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| 639 | n = _next[n]; |
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| 640 | } |
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| 641 | return num; |
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| 642 | } |
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| 643 | |
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| 644 | ///Return true if there is not active item on level \c l. |
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| 645 | bool activeFree(int l) const { |
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| 646 | return _first[l] == INVALID || !_active[_first[l]]; |
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| 647 | } |
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| 648 | |
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| 649 | ///Return the maximum allowed level. |
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| 650 | int maxLevel() const { |
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| 651 | return _max_level; |
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| 652 | } |
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| 653 | |
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| 654 | ///\name Highest Active Item |
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| 655 | ///Functions for working with the highest level |
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| 656 | ///active item. |
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| 657 | |
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| 658 | ///@{ |
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| 659 | |
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| 660 | ///Return a highest level active item. |
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| 661 | |
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| 662 | ///Return a highest level active item. |
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| 663 | /// |
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| 664 | ///\return the highest level active item or INVALID if there is no |
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| 665 | ///active item. |
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| 666 | Item highestActive() const { |
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| 667 | return _highest_active >= 0 ? _first[_highest_active] : INVALID; |
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| 668 | } |
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| 669 | |
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| 670 | ///Return a highest active level. |
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| 671 | |
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| 672 | ///Return a highest active level. |
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| 673 | /// |
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| 674 | ///\return the level of the highest active item or -1 if there is |
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| 675 | ///no active item. |
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| 676 | int highestActiveLevel() const { |
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| 677 | return _highest_active; |
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| 678 | } |
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| 679 | |
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| 680 | ///Lift the highest active item by one. |
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| 681 | |
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| 682 | ///Lift the item returned by highestActive() by one. |
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| 683 | /// |
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| 684 | void liftHighestActive() { |
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| 685 | Item i = _first[_highest_active]; |
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| 686 | if (_next[i] != INVALID) { |
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| 687 | _prev.set(_next[i], INVALID); |
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| 688 | _first[_highest_active] = _next[i]; |
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| 689 | } else { |
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| 690 | _first[_highest_active] = INVALID; |
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| 691 | _last[_highest_active] = INVALID; |
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| 692 | } |
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| 693 | _level.set(i, ++_highest_active); |
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| 694 | if (_first[_highest_active] == INVALID) { |
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| 695 | _first[_highest_active] = i; |
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| 696 | _last[_highest_active] = i; |
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| 697 | _prev.set(i, INVALID); |
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| 698 | _next.set(i, INVALID); |
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| 699 | } else { |
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| 700 | _prev.set(_first[_highest_active], i); |
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| 701 | _next.set(i, _first[_highest_active]); |
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| 702 | _first[_highest_active] = i; |
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| 703 | } |
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| 704 | } |
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| 705 | |
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| 706 | ///Lift the highest active item. |
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| 707 | |
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| 708 | ///Lift the item returned by highestActive() to level \c new_level. |
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| 709 | /// |
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| 710 | ///\warning \c new_level must be strictly higher |
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| 711 | ///than the current level. |
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| 712 | /// |
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| 713 | void liftHighestActive(int new_level) { |
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| 714 | Item i = _first[_highest_active]; |
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| 715 | if (_next[i] != INVALID) { |
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| 716 | _prev.set(_next[i], INVALID); |
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| 717 | _first[_highest_active] = _next[i]; |
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| 718 | } else { |
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| 719 | _first[_highest_active] = INVALID; |
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| 720 | _last[_highest_active] = INVALID; |
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| 721 | } |
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| 722 | _level.set(i, _highest_active = new_level); |
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| 723 | if (_first[_highest_active] == INVALID) { |
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| 724 | _first[_highest_active] = _last[_highest_active] = i; |
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| 725 | _prev.set(i, INVALID); |
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| 726 | _next.set(i, INVALID); |
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| 727 | } else { |
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| 728 | _prev.set(_first[_highest_active], i); |
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| 729 | _next.set(i, _first[_highest_active]); |
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| 730 | _first[_highest_active] = i; |
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| 731 | } |
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| 732 | } |
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| 733 | |
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| 734 | ///Lift the highest active to top. |
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| 735 | |
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| 736 | ///Lift the item returned by highestActive() to the top level and |
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| 737 | ///deactivates the node. |
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| 738 | /// |
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| 739 | void liftHighestActiveToTop() { |
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| 740 | Item i = _first[_highest_active]; |
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| 741 | _level.set(i, _max_level); |
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| 742 | if (_next[i] != INVALID) { |
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| 743 | _prev.set(_next[i], INVALID); |
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| 744 | _first[_highest_active] = _next[i]; |
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| 745 | } else { |
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| 746 | _first[_highest_active] = INVALID; |
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| 747 | _last[_highest_active] = INVALID; |
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| 748 | } |
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| 749 | while (_highest_active >= 0 && activeFree(_highest_active)) |
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| 750 | --_highest_active; |
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| 751 | } |
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| 752 | |
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| 753 | ///@} |
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| 754 | |
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| 755 | ///\name Active Item on Certain Level |
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| 756 | ///Functions for working with the active items. |
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| 757 | |
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| 758 | ///@{ |
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| 759 | |
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| 760 | ///Returns an active item on level \c l. |
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| 761 | |
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| 762 | ///Returns an active item on level \c l. |
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| 763 | /// |
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| 764 | ///Returns an active item on level \c l or \ref INVALID if there is no such |
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| 765 | ///an item. (\c l must be from the range [0...\c max_level]. |
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| 766 | Item activeOn(int l) const |
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| 767 | { |
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| 768 | return _active[_first[l]] ? _first[l] : INVALID; |
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| 769 | } |
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| 770 | |
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| 771 | ///Lifts the active item returned by \c activeOn() member function. |
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| 772 | |
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| 773 | ///Lifts the active item returned by \c activeOn() member function |
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| 774 | ///by one. |
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| 775 | Item liftActiveOn(int l) |
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| 776 | { |
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| 777 | Item i = _first[l]; |
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| 778 | if (_next[i] != INVALID) { |
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| 779 | _prev.set(_next[i], INVALID); |
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| 780 | _first[l] = _next[i]; |
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| 781 | } else { |
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| 782 | _first[l] = INVALID; |
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| 783 | _last[l] = INVALID; |
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| 784 | } |
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| 785 | _level.set(i, ++l); |
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| 786 | if (_first[l] == INVALID) { |
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| 787 | _first[l] = _last[l] = i; |
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| 788 | _prev.set(i, INVALID); |
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| 789 | _next.set(i, INVALID); |
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| 790 | } else { |
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| 791 | _prev.set(_first[l], i); |
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| 792 | _next.set(i, _first[l]); |
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| 793 | _first[l] = i; |
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| 794 | } |
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| 795 | if (_highest_active < l) { |
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| 796 | _highest_active = l; |
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| 797 | } |
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| 798 | } |
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| 799 | |
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| 800 | /// \brief Lifts the active item returned by \c activeOn() member function. |
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| 801 | /// |
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| 802 | /// Lifts the active item returned by \c activeOn() member function |
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| 803 | /// to the given level. |
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| 804 | void liftActiveOn(int l, int new_level) |
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| 805 | { |
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| 806 | Item i = _first[l]; |
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| 807 | if (_next[i] != INVALID) { |
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| 808 | _prev.set(_next[i], INVALID); |
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| 809 | _first[l] = _next[i]; |
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| 810 | } else { |
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| 811 | _first[l] = INVALID; |
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| 812 | _last[l] = INVALID; |
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| 813 | } |
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| 814 | _level.set(i, l = new_level); |
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| 815 | if (_first[l] == INVALID) { |
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| 816 | _first[l] = _last[l] = i; |
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| 817 | _prev.set(i, INVALID); |
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| 818 | _next.set(i, INVALID); |
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| 819 | } else { |
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| 820 | _prev.set(_first[l], i); |
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| 821 | _next.set(i, _first[l]); |
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| 822 | _first[l] = i; |
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| 823 | } |
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| 824 | if (_highest_active < l) { |
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| 825 | _highest_active = l; |
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| 826 | } |
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| 827 | } |
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| 828 | |
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| 829 | ///Lifts the active item returned by \c activeOn() member function. |
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| 830 | |
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| 831 | ///Lifts the active item returned by \c activeOn() member function |
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| 832 | ///to the top level. |
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| 833 | void liftActiveToTop(int l) |
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| 834 | { |
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| 835 | Item i = _first[l]; |
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| 836 | if (_next[i] != INVALID) { |
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| 837 | _prev.set(_next[i], INVALID); |
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| 838 | _first[l] = _next[i]; |
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| 839 | } else { |
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| 840 | _first[l] = INVALID; |
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| 841 | _last[l] = INVALID; |
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| 842 | } |
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| 843 | _level.set(i, _max_level); |
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| 844 | if (l == _highest_active) { |
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| 845 | while (_highest_active >= 0 && activeFree(_highest_active)) |
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| 846 | --_highest_active; |
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| 847 | } |
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| 848 | } |
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| 849 | |
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| 850 | ///@} |
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| 851 | |
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| 852 | /// \brief Lift an active item to a higher level. |
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| 853 | /// |
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| 854 | /// Lift an active item to a higher level. |
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| 855 | /// \param i The item to be lifted. It must be active. |
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| 856 | /// \param new_level The new level of \c i. It must be strictly higher |
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| 857 | /// than the current level. |
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| 858 | /// |
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| 859 | void lift(Item i, int new_level) { |
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| 860 | if (_next[i] != INVALID) { |
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| 861 | _prev.set(_next[i], _prev[i]); |
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| 862 | } else { |
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| 863 | _last[new_level] = _prev[i]; |
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| 864 | } |
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| 865 | if (_prev[i] != INVALID) { |
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| 866 | _next.set(_prev[i], _next[i]); |
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| 867 | } else { |
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| 868 | _first[new_level] = _next[i]; |
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| 869 | } |
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| 870 | _level.set(i, new_level); |
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| 871 | if (_first[new_level] == INVALID) { |
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| 872 | _first[new_level] = _last[new_level] = i; |
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| 873 | _prev.set(i, INVALID); |
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| 874 | _next.set(i, INVALID); |
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| 875 | } else { |
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| 876 | _prev.set(_first[new_level], i); |
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| 877 | _next.set(i, _first[new_level]); |
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| 878 | _first[new_level] = i; |
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| 879 | } |
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| 880 | if (_highest_active < new_level) { |
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| 881 | _highest_active = new_level; |
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| 882 | } |
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| 883 | } |
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| 884 | |
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| 885 | ///Lift all nodes on and above a level to the top (and deactivate them). |
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| 886 | |
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| 887 | ///This function lifts all nodes on and above level \c l to \c |
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| 888 | ///maxLevel(), and also deactivates them. |
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| 889 | void liftToTop(int l) { |
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| 890 | for (int i = l + 1; _first[i] != INVALID; ++i) { |
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| 891 | Item n = _first[i]; |
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| 892 | while (n != INVALID) { |
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| 893 | _level.set(n, _max_level); |
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| 894 | n = _next[n]; |
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| 895 | } |
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| 896 | _first[i] = INVALID; |
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| 897 | _last[i] = INVALID; |
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| 898 | } |
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| 899 | if (_highest_active > l - 1) { |
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| 900 | _highest_active = l - 1; |
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| 901 | while (_highest_active >= 0 && activeFree(_highest_active)) |
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| 902 | --_highest_active; |
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| 903 | } |
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| 904 | } |
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| 905 | |
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| 906 | private: |
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| 907 | |
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| 908 | int _init_level; |
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| 909 | |
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| 910 | public: |
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| 911 | |
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| 912 | ///\name Initialization |
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| 913 | ///Using this function you can initialize the levels of the item. |
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| 914 | ///\n |
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| 915 | ///This initializatios is started with calling \c initStart(). |
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| 916 | ///Then the |
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| 917 | ///items should be listed levels by levels statring with the lowest one |
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| 918 | ///(with level 0). This is done by using \c initAddItem() |
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| 919 | ///and \c initNewLevel(). Finally \c initFinish() must be called. |
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| 920 | ///The items not listed will be put on the highest level. |
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| 921 | ///@{ |
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| 922 | |
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| 923 | ///Start the initialization process. |
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| 924 | |
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| 925 | void initStart() { |
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| 926 | |
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| 927 | for (int i = 0; i <= _max_level; ++i) { |
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| 928 | _first[i] = _last[i] = INVALID; |
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| 929 | } |
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| 930 | _init_level = 0; |
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| 931 | for(typename ItemSetTraits<Graph,Item>::ItemIt i(_graph); |
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| 932 | i != INVALID; ++i) { |
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| 933 | _level.set(i, _max_level); |
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| 934 | } |
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| 935 | } |
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| 936 | |
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| 937 | ///Add an item to the current level. |
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| 938 | |
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| 939 | void initAddItem(Item i) { |
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| 940 | _level.set(i, _init_level); |
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| 941 | if (_last[_init_level] == INVALID) { |
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| 942 | _first[_init_level] = i; |
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| 943 | _last[_init_level] = i; |
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| 944 | _prev.set(i, INVALID); |
---|
| 945 | _next.set(i, INVALID); |
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| 946 | } else { |
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| 947 | _prev.set(i, _last[_init_level]); |
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| 948 | _next.set(i, INVALID); |
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| 949 | _next.set(_last[_init_level], i); |
---|
| 950 | _last[_init_level] = i; |
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| 951 | } |
---|
| 952 | } |
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| 953 | |
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| 954 | ///Start a new level. |
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| 955 | |
---|
| 956 | ///Start a new level. |
---|
| 957 | ///It shouldn't be used before the items on level 0 are listed. |
---|
| 958 | void initNewLevel() { |
---|
| 959 | ++_init_level; |
---|
| 960 | } |
---|
| 961 | |
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| 962 | ///Finalize the initialization process. |
---|
| 963 | |
---|
| 964 | void initFinish() { |
---|
| 965 | _highest_active = -1; |
---|
| 966 | } |
---|
| 967 | |
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| 968 | ///@} |
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| 969 | |
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| 970 | }; |
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| 971 | |
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| 972 | |
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[2346] | 973 | } //END OF NAMESPACE LEMON |
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| 974 | |
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| 975 | #endif |
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| 976 | |
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