POJ 1466 Girls and Boys (匈牙利算法 最大独立集)

#include <cstdio>
#include <cstring>
int const MAX = 505;
bool g[MAX][MAX];
bool vis[MAX];
int cx[MAX], cy[MAX];
int n;

int DFS(int x)
{
    for(int y = 0; y < n; y++)
    {
        if(!vis[y] && g[x][y])
        {
            vis[y] = true;
            if(cy[y] == -1 || DFS(cy[y]))
            {
                cy[y] = x;
                cx[x] = y;
                return 1;
            }
        }
    }
    return 0;
}

int MaxMatch()
{
    memset(cx, -1, sizeof(cx));
    memset(cy, -1, sizeof(cy));
    int res = 0;
    for(int i = 0; i < n; i++)
    {
        if(cx[i] == -1)
        {
            memset(vis, false, sizeof(vis));
            res += DFS(i);
        }
    }
    return res;
}

int main()
{
    while(scanf("%d", &n) != EOF)
    {
        memset(g, false, sizeof(g));
        for(int i = 0; i < n; i++)
        {
            int x;
            scanf("%d", &x);
            int num;
            scanf(": (%d)", &num);
            for(int j = 0; j < num; j++)
            {
                int y;
                scanf("%d", &y);
                g[x][y] = true;
            }
        }
        int ans = MaxMatch();
        printf("%d\n", n - ans / 2);
    }
}