二分图匹配模板

//#include<stdio.h>#include<vector>#include<string.h>#define MaxN 510using namespace std;int from[MaxN];vector<int> g[MaxN];bool used[MaxN];bool match(int num){int i;for(i = 0; i < g[num].size(); i++){if(!used[g[num][i]]){used[g[num][i]] = true;if(from[g[num][i]] == 0 || match(from[g[num][i]])){from[g[num][i]] = num;return true;}}}return false;}int hungary(int n){int i;int tot = 0;memset(from, 0, sizeof(from));for( i = 1; i <=n; i++){memset(used, 0, sizeof(used));if(match(i))tot ++;}return tot;}//如果要a-b加一条边，则 g[a].push_back(b);