洛谷 P1551 亲戚（并查集模板）

 1 #include<cstdio>
 2 #include<iostream>
 3 
 4 using namespace std;
 5 
 6 int f[10000005];
 7 int a, b, c, d;
 8 
 9 inline int find(int x){
10     if(f[x] != x)
11         f[x] = find(f[x]);
12     return f[x];
13 } //“查”操作 
14 int main(){
15     int n, m, p;
16     scanf("%d%d%d", &n, &m, &p);
17     for(int i = 1; i <= n; i++)
18         f[i] = i;
19     for(int i = 1; i <= m; i++){
20         scanf("%d%d", &a, &b);
21         int r1 = find(a);
22         int r2 = find(b);
23         if(r1 != r2) 
24             f[r1] = r2; //“并”操作 
25     }
26     for(int i = 1; i <= p; i++){
27         scanf("%d%d", &c, &d);
28         int f1 = find(c);
29         int f2 = find(d);
30         if(f1 == f2) printf("Yes\n");
31         else printf("No\n");
32     }
33     return 0;
34 }