BZOJ [ZJOI2007]矩阵游戏(二分图匹配)

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 #define clr(a,val) memset(a,val,sizeof a)
 4 #define PI acos(-1.0)
 5 #define eps 1e-6
 6 #define lowbit(x) x&-x
 7 typedef long long ll;
 8 const int INF=0x3f3f3f3f;
 9 const int maxn=2010;
10 int vis[maxn],g[maxn][maxn];
11 int T,n,x,match[maxn],ans;
12 
13 bool dfs(int u,int N)
14 {
15     for(int i=1;i<=N;i++)
16     {
17         if(vis[i] || !g[u][i]) continue;
18         vis[i] = 1;
19         if(!match[i] || dfs(match[i],N))
20         {
21             match[i]=u;
22             return true;
23         }
24     }
25     return false;
26 }
27 int main()
28 {
29     scanf("%d",&T);
30     while(T--)
31     {
32         scanf("%d",&n);
33         for(int i=1;i<=n;++i)
34         {
35             for(int j=1;j<=n;++j) scanf("%d",&g[i][j]);
36         }
37         clr(match,0);ans=0;
38         for(int i=1;i<=n;++i) 
39         {
40             clr(vis,0); 
41             if(dfs(i,n)) ans++;
42         }
43         if(ans==n) puts("Yes");
44         else puts("No");    
45     }
46     return 0;
47 }