46 lines
1.2 KiB
C++
46 lines
1.2 KiB
C++
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#include <bits/stdc++.h>
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using namespace std;
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const int N = 5010;
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int n; //n个人
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int m; //m个亲戚
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int p; //询问p对亲戚关系
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int x, y; //输入两个人之间的关系
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int fa[N]; //并查集数组
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//要深入理解这个递归并压缩的过程
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int find(int x) {
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if (fa[x] != x)//如果x不是族长,递归找父亲,副产品就是找回的结果更新掉自己的家族信息。
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fa[x] = find(fa[x]);//非常经典的更新,路径压缩大法！
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//返回族长是谁
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return fa[x];
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}
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//加入家族集合中
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void join(int c1, int c2) {
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int f1 = find(c1), f2 = find(c2);
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if (f1 != f2)fa[f1] = f2;//各自找家长，如果家长不一样，就把C1的族长，认C2的族长为爸爸,C1的族长强烈表示不满意
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}
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int main() {
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cin >> n >> m >> p;
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//并查集初始化
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for (int i = 1; i <= n; i++)fa[i] = i; //自己是自己的老大
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//录入m种关系
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for (int i = 1; i <= m; i++) {
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cin >> x >> y;
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//加入并查集
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join(x, y);
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}
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//处理p次询问
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while (p--) {
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cin >> x >> y;
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if (find(x) == find(y)) cout << "Yes" << endl;
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else cout << "No" << endl;
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}
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return 0;
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}
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