POJ 1469 COURSES

题目链接：POJ 1469 COURSES

题目大意：

题解：
二分图匹配模板。

#include <cstring>
#include <iostream>
#include <cstdio>
using namespace std;

int t, p, n, link[310], ans, cnt, head[310];
bool vis[310];
struct Edge {
    int v, next;
} edge[30010];

void addEdge(int u, int v) {
    edge[++cnt].v = v;
    edge[cnt].next = head[u];
    head[u] = cnt;
}

bool hungry(int u) {
    for (int i = head[u]; i; i = edge[i].next) {
        int v = edge[i].v;
        if (!vis[v]) {
            vis[v] = true;
            if (!link[v] || hungry(link[v])) {
                link[v] = u;
                return true;
            }
        }
    }
    return false;
}

int main() {
    scanf("%d", &t);
    while (t--) {
        scanf("%d%d", &p, &n);
        cnt = 0;
        memset(head, 0, sizeof(head));
        memset(link, 0, sizeof(link));
        for (int i = 1, k, x; i <= p; ++i) {
            scanf("%d", &k);
            while (k--) {
                scanf("%d", &x);
                addEdge(i, x);
            }
        }
        ans = 0;
        for (int i = 1; i <= p; ++i) {
            memset(vis, 0, sizeof(vis));
            ans += hungry(i);
        }
        if (ans == p) {
            puts("YES");
        } else {
            puts("NO");
        }
    }
    return 0;
}

标签：head,int,310,cnt,COURSES,edge,POJ,link,1469
来源： https://www.cnblogs.com/IzumiSagiri/p/15857574.html