差点翻车
题目
dbzoj
题解
我居然一开始傻逼了
后来发现黑点的x, y连边就是一个二分图,
然后跑最大匹配看看是不是n就行了
代码
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
| #include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#define MAXN (200)
using namespace std;
int n, link[MAXN + 5], ans;
bool vis[MAXN + 5], edg[MAXN + 5][MAXN + 5];
int find(int now) {
for (int i = 1; i <= n; i++)
if (!vis[i] && edg[now][i]) {
vis[i] = true;
if (!link[i] || find(link[i])) {
link[i] = now;
return true;
}
}
return false;
}
int main() {
int t;
scanf("%d", &t);
while (t--) {
memset(link, 0, sizeof(link));
memset(edg, false, sizeof(edg));
scanf("%d", &n);
for (int i = 1; i <= n; i++)
for (int j = 1, x; j <= n; j++)
scanf("%d", &x), edg[i][j] = (x != 0);
ans = 0;
for (int i = 1; i <= n; i++) {
memset(vis, false, sizeof(vis));
if (find(i)) ++ans;
}
puts((ans == n) ? "Yes" : "No");
}
return 0;
}
|
By Cansult