HDOJ 1083 Hungarian实现

#include<cstdio>
#include<vector>

using namespace std;

#define N1 100
#define N2 300

int match[N2];
vector<int> graph[N1];
bool visit[N2];

bool hungarian(int u){
    for (auto i = graph[u].begin(); i != graph[u].end(); i++)
        if (!visit[*i]){
            visit[*i] = 1;
            if (match[*i] == -1 || hungarian(match[*i])){
                match[*i] = u;
                return true;
            }
        }
    return false;
}

int main(){
    int m;
    scanf("%d", &m);
    for (int i = 0; i < m; i++){
        int p, n;
        bool flag = 0;
        scanf("%d %d", &p, &n);
        for (int j = 0; j < p; j++){
            int num;
            scanf("%d", &num);
            graph[j].clear();
            for (int l = 0; l < num; l++){
                int student;
                scanf("%d", &student);
                graph[j].push_back(student - 1);
            }
        }
        for (int j = 0; j < n; j++)
            match[j] = -1;
        for (int j = 0; j < p; j++){
            for (int l = 0; l < n; l++)
                visit[l] = 0;
            if (!hungarian(j)){
                flag = 1;
                break;
            }
        }
        if (flag)
            printf("NO
");
        else
            printf("YES
");
    }
    return 0;
}