棋盘游戏---hdu1281（最大匹配）

#include<stdio.h>
#include<string.h>
#include<iostream>
#include<algorithm>
using namespace std;
#define N 110

int maps[N][N], vis[N], used[N], n, m, k, ans, ans0;
struct node
{
    int x,y;
}a[N*N];///注意k的取值范围，wa了一次；
bool Find(int u)
{
    for(int i=1; i<=m; i++)
    {
        if(!vis[i] && maps[u][i])
        {
            vis[i] = 1;
            if(!used[i] || Find(used[i]))
            {
                used[i] = u;
                return true;
            }
        }
    }
    return false;
}

int main()
{
    int t = 1, x, y;
    while(scanf("%d%d%d", &n, &m, &k)!=EOF)
    {
        ans = ans0 = 0;
        memset(used, 0, sizeof(used));
        memset(maps, 0, sizeof(maps));
        for(int i=1; i<=k; i++)
        {
            scanf("%d%d", &x, &y);
            a[i].x = x;
            a[i].y = y;
            maps[x][y] = 1;
        }
        for(int i=1; i<=n; i++)
        {
            memset(vis, 0, sizeof(vis));
            if(Find(i))
                ans++;
        }
        for(int i=1; i<=k; i++)
        {
            int kk=0;
            memset(used, 0, sizeof(used));
            x=a[i].x;
            y=a[i].y;
            maps[x][y] = 0;
            for(int j=1; j<=n; j++)
            {
                memset(vis, 0, sizeof(vis));
                if(Find(j))
                    kk++;
            }
            if(kk<ans)
                ans0++;
            maps[x][y] = 1;
        }
        printf("Board %d have %d important blanks for %d chessmen.\n", t++, ans0, ans);
    }
    return 0;
}