因为并查集一开始自己是自己的上级关系
by InversionShadow @ 2023-04-05 22:10:31
```
#include <iostream>
using namespace std;
void init(int n, int *fa) {
for (int i = 1; i <= n; ++i)
fa[i] = i;
return;
}
int find(int x, int *fa) {
if (x == fa[x])
return x; // 如果x的父亲就是x那么就是找到了x的祖先节点
return find(fa[x], fa); // 递归返回
}
void merge(int a, int b, int *fa) {
a = find(a, fa);
b = find(b, fa);
if (a != b)
fa[b] = a; // 如果两个元素不相等就让一个元素成为另一个元素的父节点
return;
}
int main() {
int person, relation, ask;
cin >> person >> relation >> ask;
int PR[person + 1];// 角标是从 1开始
init(person, PR);
while (relation--) {
int relative1, relative2;
cin >> relative1 >> relative2;
merge(relative1, relative2, PR);
}
while (ask--) {
int person1, person2;
cin >> person1 >> person2;
int ancestor1 = find(person1, PR);// 找祖宗
int ancestor2 = find(person2, PR);
if (ancestor1 == ancestor2)
cout << "Yes" << endl;
else
cout << "No" << endl;
}
return 0;
}
```
by siaosan @ 2023-06-07 21:03:46