1 | /* -*- C++ -*- |
---|
2 | * |
---|
3 | * This file is a part of LEMON, a generic C++ optimization library |
---|
4 | * |
---|
5 | * Copyright (C) 2003-2008 |
---|
6 | * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport |
---|
7 | * (Egervary Research Group on Combinatorial Optimization, EGRES). |
---|
8 | * |
---|
9 | * Permission to use, modify and distribute this software is granted |
---|
10 | * provided that this copyright notice appears in all copies. For |
---|
11 | * precise terms see the accompanying LICENSE file. |
---|
12 | * |
---|
13 | * This software is provided "AS IS" with no warranty of any kind, |
---|
14 | * express or implied, and with no claim as to its suitability for any |
---|
15 | * purpose. |
---|
16 | * |
---|
17 | */ |
---|
18 | |
---|
19 | #ifndef LEMON_BITS_LP_SOLVER_ID_H |
---|
20 | #define LEMON_BITS_LP_SOLVER_ID_H |
---|
21 | |
---|
22 | namespace lemon { |
---|
23 | |
---|
24 | namespace _lp_bits { |
---|
25 | |
---|
26 | struct LpIdImpl { |
---|
27 | std::vector<int> index; |
---|
28 | std::vector<int> cross; |
---|
29 | int first_index; |
---|
30 | int first_free; |
---|
31 | }; |
---|
32 | |
---|
33 | class LpId { |
---|
34 | public: |
---|
35 | |
---|
36 | class IdHandler { |
---|
37 | public: |
---|
38 | virtual ~IdHandler() {} |
---|
39 | virtual int addId(LpIdImpl&) = 0; |
---|
40 | virtual void eraseId(LpIdImpl&, int xn) = 0; |
---|
41 | }; |
---|
42 | |
---|
43 | LpId(int min_index = 0) { |
---|
44 | id_handler = 0; |
---|
45 | impl.first_free = -1; |
---|
46 | impl.first_index = min_index; |
---|
47 | impl.cross.resize(impl.first_index); |
---|
48 | } |
---|
49 | |
---|
50 | void setIdHandler(IdHandler& ih) { |
---|
51 | id_handler = &ih; |
---|
52 | } |
---|
53 | |
---|
54 | int fixId(int fn) const {return impl.cross[fn];} |
---|
55 | int floatingId(int xn) const {return impl.index[xn];} |
---|
56 | |
---|
57 | int addId() { |
---|
58 | if (id_handler == 0) { |
---|
59 | int xn, fn = impl.cross.size(); |
---|
60 | if (impl.first_free == -1) { |
---|
61 | xn = impl.index.size(); |
---|
62 | impl.index.push_back(fn); |
---|
63 | } else { |
---|
64 | xn = impl.first_free; |
---|
65 | impl.first_free = impl.index[impl.first_free]; |
---|
66 | impl.index[xn] = fn; |
---|
67 | } |
---|
68 | impl.cross.push_back(xn); |
---|
69 | return xn; |
---|
70 | } else { |
---|
71 | return id_handler->addId(impl); |
---|
72 | } |
---|
73 | } |
---|
74 | |
---|
75 | void eraseId(int xn) { |
---|
76 | if (id_handler == 0) { |
---|
77 | int fn = impl.index[xn]; |
---|
78 | impl.index[xn] = impl.first_free; |
---|
79 | impl.first_free = xn; |
---|
80 | for(int i = fn + 1; i < int(impl.cross.size()); ++i) { |
---|
81 | impl.cross[i - 1] = impl.cross[i]; |
---|
82 | impl.index[impl.cross[i]]--; |
---|
83 | } |
---|
84 | impl.cross.pop_back(); |
---|
85 | } else { |
---|
86 | id_handler->eraseId(impl, xn); |
---|
87 | } |
---|
88 | } |
---|
89 | |
---|
90 | void firstFloating(int& fn) const { |
---|
91 | fn = impl.first_index; |
---|
92 | if (fn == int(impl.cross.size())) fn = -1; |
---|
93 | } |
---|
94 | |
---|
95 | void nextFloating(int& fn) const { |
---|
96 | ++fn; |
---|
97 | if (fn == int(impl.cross.size())) fn = -1; |
---|
98 | } |
---|
99 | |
---|
100 | void firstFix(int& xn) const { |
---|
101 | int fn; |
---|
102 | firstFloating(fn); |
---|
103 | xn = fn != -1 ? fixId(fn) : -1; |
---|
104 | } |
---|
105 | |
---|
106 | void nextFix(int& xn) const { |
---|
107 | int fn = floatingId(xn); |
---|
108 | nextFloating(fn); |
---|
109 | xn = fn != -1 ? fixId(fn) : -1; |
---|
110 | } |
---|
111 | |
---|
112 | protected: |
---|
113 | LpIdImpl impl; |
---|
114 | IdHandler *id_handler; |
---|
115 | }; |
---|
116 | |
---|
117 | class RelocateIdHandler : public LpId::IdHandler { |
---|
118 | public: |
---|
119 | |
---|
120 | virtual int addId(LpIdImpl& impl) { |
---|
121 | int xn, fn = impl.cross.size(); |
---|
122 | if (impl.first_free == -1) { |
---|
123 | xn = impl.index.size(); |
---|
124 | impl.index.push_back(fn); |
---|
125 | } else { |
---|
126 | xn = impl.first_free; |
---|
127 | impl.first_free = impl.index[impl.first_free]; |
---|
128 | impl.index[xn] = fn; |
---|
129 | } |
---|
130 | impl.cross.push_back(xn); |
---|
131 | return xn; |
---|
132 | } |
---|
133 | |
---|
134 | virtual void eraseId(LpIdImpl& impl, int xn) { |
---|
135 | int fn = impl.index[xn]; |
---|
136 | impl.index[xn] = impl.first_free; |
---|
137 | impl.first_free = xn; |
---|
138 | impl.cross[fn] = impl.cross.back(); |
---|
139 | impl.index[impl.cross.back()] = fn; |
---|
140 | impl.cross.pop_back(); |
---|
141 | } |
---|
142 | }; |
---|
143 | } |
---|
144 | } |
---|
145 | |
---|
146 | #endif |
---|