marrige problem

// Project 1// Design and Analysis of Algorithms CSCI-335// Yu Zhiqiang 2013.11.20#include <iostream>#include <cstring>#include <algorithm>#include <map>#include <string>#include <vector>#include <set>using namespace std;const int MAXN = 1024;int n;                // X 的大小int weight[MAXN][MAXN];        // X 到 Y 的映射（权重）int lx[MAXN], ly[MAXN];        // 标号bool sx[MAXN], sy[MAXN];    // 是否被搜索过int match[MAXN];        // Y(i) 与 X(match [i]) 匹配map<string, int> name_to_id;vector<string> id_to_name;set<int> boy;bool path(int u) {sx[u] = true;for (int v = 0; v < n; v++)if (!sy[v] && lx[u] + ly[v] == weight[u][v]) {sy[v] = true;if (match[v] == -1 || path(match[v])) {match[v] = u;return true;}}return false;}int bestmatch() {int i, j;// 初始化标号for (i = 0; i < n; i++) {lx[i] = -0x1FFFFFFF;ly[i] = 0;for (j = 0; j < n; j++)if (lx[i] < weight[i][j])lx[i] = weight[i][j];}memset(match, -1, sizeof(match));for (int u = 0; u < n; u++)while (1) {memset(sx, 0, sizeof(sx));memset(sy, 0, sizeof(sy));if (path(u))break;// 修改标号int dx = 0x7FFFFFFF;for (i = 0; i < n; i++)if (sx[i])for (j = 0; j < n; j++)if (!sy[j])dx = min(lx[i] + ly[j] - weight[i][j], dx);for (i = 0; i < n; i++) {if (sx[i])lx[i] -= dx;if (sy[i])ly[i] += dx;}}int sum = 0;for (i = 0; i < n; i++)sum += weight[match[i]][i];return sum;}inline int get_id(string name) {if (name_to_id.find(name) == name_to_id.end()) {int new_id = name_to_id.size();name_to_id[name] = new_id;id_to_name.push_back(name);return new_id;} else {return name_to_id[name];}}inline string get_name(int id) {return id_to_name[id];}void init() {for(int i=0; i<MAXN; i++) {for(int j=0; j<MAXN;j++) {weight[i][j] = -1e5;}}string name1, name2;int w;while (cin >> name1 >> name2 >> w and w) {int id1 = get_id(name1);int id2 = get_id(name2);boy.insert(id1);cerr << id1 << " " << id2 << endl;weight[id1][id2] = w;weight[id2][id1] = w;}n = name_to_id.size();}int main() {init();cout << bestmatch()/2 << endl;int sum=0;for (int i = 0; i < n; i++)if(boy.find(i) != boy.end()) {sum += weight[i][match[i]];cerr << weight[i][match[i]] << " " << get_name(i) << " -> " << get_name(match[i]) << endl;}cout << sum << endl;return 0;}