题目大意：
判断序列是不是拓扑排序

代码:

#include <iostream>
#include <vector>
using namespace std;
int main() {int n, m, a, b, k, flag = 0, in[1010];vector<int> v[1010];scanf("%d %d", &n, &m);for (int i = 0; i < m; i++){scanf("%d %d", &a, &b);v[a].push_back(b);in[b]++;}scanf("%d", &k);for (int i = 0; i < k; i++) {int judge = 1;vector<int> tin(in, in+n+1);for (int j = 0; j < n; j++) {scanf("%d", &a);if (tin[a] != 0) judge = 0;for (int it : v[a]) tin[it]--;}if (judge == 1) continue;printf("%s%d", flag == 1 ? " ": "", i);flag = 1;}return 0;
}