HDU

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=2063

题意：中文题。

思路：这就是匈牙利算法算二分图最大匹配的算法，具体思想可以参考这个博客，我觉得很不错：http://blog.csdn.net/dark_scope/article/details/8880547

代码：

#include <cstdio>#include <cmath>#include <iostream>#include <cstring>#include <algorithm>#include <queue>#include <stack>#include <vector>#include <map>#include <numeric>#include <set>#include <string>#include <cctype>#include <sstream>#define INF 0x3f3f3f3fusing namespace std;typedef long long LL;typedef pair<LL, LL> P;const int maxn = 1e5 + 5;const int mod = 1e8 + 7;int k,m,n;int G[505][505];int vis[505],used[505];bool Find(int x){    for (int i=1;i<=n;i++){        if (!vis[i]&&G[x][i]){            vis[i]=1;            if (!used[i]||Find(used[i])){                used[i]=x;                return 1;            }        }    }    return 0;}int main() {    while (~scanf ("%d%d%d",&k,&m,&n)&&k){        memset(G,0,sizeof(G));        memset(used,0,sizeof(used));        while (k--){            int u,v;            scanf ("%d%d",&u,&v);            G[u][v]=1;        }        int ans=0;        for (int i=1;i<=m;i++){            memset(vis,0,sizeof(vis));            if (Find(i)) ans++;        }        printf ("%d\n",ans);    }    return 0;}