传送门

裸匈牙利算法
然后这个题就是很坑（这里边没说要多组数据，但是他！！！！有多组数据，然后， 他还卡longlong）
有些气愤，挑了好长时间的

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <iomanip>
#define int long long

using namespace std;
int a[501][501], v[501], match[501];
int k, m, n, ans;

int read() {
    int s = 0,f = 0;
    char ch = getchar();
    while (!isdigit(ch)) f |= (ch == '-'), ch = getchar();
    while (isdigit(ch)) s = s * 10 + (ch ^ 48), ch = getchar();
    return f ? -s : s;
}

bool go(int u) {
    for (int i = 1; i <= m; i++)
        if (a[u][i] && !v[i]) {
            v[i] = true;
            if (!match[i] || go(match[i])) {
                match[i] = u;
                return 1;
            }
        }
    return 0;
}

signed main() {
    scanf("%d", &k);
    while (k != 0) {
        n = read(), m = read();
        int x, y;
        for (int i = 1; i <= k; i++) {
            x = read(), y = read();
            a[x][y] = 1;
        }
        for (int i = 1; i <= n; i++) {
            memset(v, 0, sizeof(v));
            if (go(i)) ans++;
        }
        printf("%d\n",ans);
        ans = 0;
        memset(match, 0, sizeof(match));
        memset(a, 0, sizeof(a));
        scanf("%d", &k);
    }
}