注意:是课程匹配的学生,学生没课上没事.....
#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
const int MAXN = 1005;
const int oo = 1e9;
bool G[MAXN][MAXN], used[MAXN];
int p[MAXN], N, M;///n门课,M个学生
bool Find(int u)
{
for(int i=1; i<=M; i++)
{
if(G[u][i] && used[i] == false)
{
used[i] = true;
if(p[i] == false || Find(p[i]))
{
p[i] = u;
return true;
}
}
}
return false;
}
int main()
{
int T;
scanf("%d", &T);
while(T--)
{
int i, v, Q;
memset(G, 0, sizeof(G));
memset(p, 0, sizeof(p));
scanf("%d%d", &N, &M);
for(i=1; i<=N; i++)
{
scanf("%d", &Q);
while(Q--)
{
scanf("%d", &v);
G[i][v] = true;
}
}
for(i=1; i<=N; i++)
{
memset(used, false, sizeof(used));
if( Find(i) == false )
break;
}
if(i <= N)
printf("NO\n");
else
printf("YES\n");
}
return 0;
}