1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/lemon/bits/solver_bits.h Tue Dec 02 22:48:28 2008 +0100
1.3 @@ -0,0 +1,191 @@
1.4 +/* -*- mode: C++; indent-tabs-mode: nil; -*-
1.5 + *
1.6 + * This file is a part of LEMON, a generic C++ optimization library.
1.7 + *
1.8 + * Copyright (C) 2003-2008
1.9 + * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
1.10 + * (Egervary Research Group on Combinatorial Optimization, EGRES).
1.11 + *
1.12 + * Permission to use, modify and distribute this software is granted
1.13 + * provided that this copyright notice appears in all copies. For
1.14 + * precise terms see the accompanying LICENSE file.
1.15 + *
1.16 + * This software is provided "AS IS" with no warranty of any kind,
1.17 + * express or implied, and with no claim as to its suitability for any
1.18 + * purpose.
1.19 + *
1.20 + */
1.21 +
1.22 +#ifndef LEMON_BITS_SOLVER_BITS_H
1.23 +#define LEMON_BITS_SOLVER_BITS_H
1.24 +
1.25 +namespace lemon {
1.26 +
1.27 + namespace _solver_bits {
1.28 +
1.29 + class VarIndex {
1.30 + private:
1.31 + struct ItemT {
1.32 + int prev, next;
1.33 + int index;
1.34 + };
1.35 + std::vector<ItemT> items;
1.36 + int first_item, last_item, first_free_item;
1.37 +
1.38 + std::vector<int> cross;
1.39 +
1.40 + public:
1.41 +
1.42 + VarIndex()
1.43 + : first_item(-1), last_item(-1), first_free_item(-1) {
1.44 + }
1.45 +
1.46 + void clear() {
1.47 + first_item = -1;
1.48 + first_free_item = -1;
1.49 + items.clear();
1.50 + cross.clear();
1.51 + }
1.52 +
1.53 + int addIndex(int idx) {
1.54 + int n;
1.55 + if (first_free_item == -1) {
1.56 + n = items.size();
1.57 + items.push_back(ItemT());
1.58 + } else {
1.59 + n = first_free_item;
1.60 + first_free_item = items[n].next;
1.61 + if (first_free_item != -1) {
1.62 + items[first_free_item].prev = -1;
1.63 + }
1.64 + }
1.65 + items[n].index = idx;
1.66 + if (static_cast<int>(cross.size()) <= idx) {
1.67 + cross.resize(idx + 1, -1);
1.68 + }
1.69 + cross[idx] = n;
1.70 +
1.71 + items[n].prev = last_item;
1.72 + items[n].next = -1;
1.73 + if (last_item != -1) {
1.74 + items[last_item].next = n;
1.75 + } else {
1.76 + first_item = n;
1.77 + }
1.78 + last_item = n;
1.79 +
1.80 + return n;
1.81 + }
1.82 +
1.83 + int addIndex(int idx, int n) {
1.84 + while (n >= static_cast<int>(items.size())) {
1.85 + items.push_back(ItemT());
1.86 + items.back().prev = -1;
1.87 + items.back().next = first_free_item;
1.88 + if (first_free_item != -1) {
1.89 + items[first_free_item].prev = items.size() - 1;
1.90 + }
1.91 + first_free_item = items.size() - 1;
1.92 + }
1.93 + if (items[n].next != -1) {
1.94 + items[items[n].next].prev = items[n].prev;
1.95 + }
1.96 + if (items[n].prev != -1) {
1.97 + items[items[n].prev].next = items[n].next;
1.98 + } else {
1.99 + first_free_item = items[n].next;
1.100 + }
1.101 +
1.102 + items[n].index = idx;
1.103 + if (static_cast<int>(cross.size()) <= idx) {
1.104 + cross.resize(idx + 1, -1);
1.105 + }
1.106 + cross[idx] = n;
1.107 +
1.108 + items[n].prev = last_item;
1.109 + items[n].next = -1;
1.110 + if (last_item != -1) {
1.111 + items[last_item].next = n;
1.112 + } else {
1.113 + first_item = n;
1.114 + }
1.115 + last_item = n;
1.116 +
1.117 + return n;
1.118 + }
1.119 +
1.120 + void eraseIndex(int idx) {
1.121 + int n = cross[idx];
1.122 +
1.123 + if (items[n].prev != -1) {
1.124 + items[items[n].prev].next = items[n].next;
1.125 + } else {
1.126 + first_item = items[n].next;
1.127 + }
1.128 + if (items[n].next != -1) {
1.129 + items[items[n].next].prev = items[n].prev;
1.130 + } else {
1.131 + last_item = items[n].prev;
1.132 + }
1.133 +
1.134 + if (first_free_item != -1) {
1.135 + items[first_free_item].prev = n;
1.136 + }
1.137 + items[n].next = first_free_item;
1.138 + items[n].prev = -1;
1.139 + first_free_item = n;
1.140 +
1.141 + while (!cross.empty() && cross.back() == -1) {
1.142 + cross.pop_back();
1.143 + }
1.144 + }
1.145 +
1.146 + int maxIndex() const {
1.147 + return cross.size() - 1;
1.148 + }
1.149 +
1.150 + void shiftIndices(int idx) {
1.151 + for (int i = idx + 1; i < static_cast<int>(cross.size()); ++i) {
1.152 + cross[i - 1] = cross[i];
1.153 + if (cross[i] != -1) {
1.154 + --items[cross[i]].index;
1.155 + }
1.156 + }
1.157 + cross.back() = -1;
1.158 + cross.pop_back();
1.159 + while (!cross.empty() && cross.back() == -1) {
1.160 + cross.pop_back();
1.161 + }
1.162 + }
1.163 +
1.164 + void relocateIndex(int idx, int jdx) {
1.165 + cross[idx] = cross[jdx];
1.166 + items[cross[jdx]].index = idx;
1.167 + cross[jdx] = -1;
1.168 +
1.169 + while (!cross.empty() && cross.back() == -1) {
1.170 + cross.pop_back();
1.171 + }
1.172 + }
1.173 +
1.174 + int operator[](int idx) const {
1.175 + return cross[idx];
1.176 + }
1.177 +
1.178 + int operator()(int fdx) const {
1.179 + return items[fdx].index;
1.180 + }
1.181 +
1.182 + void firstItem(int& fdx) const {
1.183 + fdx = first_item;
1.184 + }
1.185 +
1.186 + void nextItem(int& fdx) const {
1.187 + fdx = items[fdx].next;
1.188 + }
1.189 +
1.190 + };
1.191 + }
1.192 +}
1.193 +
1.194 +#endif