POJ 2524 Ubiquitous Religions

合集 - POJ(9)

1.POJ 3278 Catch That Cow2024-07-092.POJ 1426 Find The Multiple2024-07-093.POJ 3126 Prime Path2024-07-134.POJ 3414 Pots2024-07-105.POJ 1077 Eight2024-07-116.POJ 1521 Entropy2024-07-127.POJ 1089 Intervals2024-07-16

8.POJ 2524 Ubiquitous Religions2024-07-16

9.POJ 2388 Who's in the Middle2024-07-26

收起

题目链接：POJ 2524 【Ubiquitous Religions】

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思路

       经典并查集模板，求集合个数。

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代码

#include <iostream>
 
using namespace std;
#define ll long long
const int N = 5e5 + 10;
 
int fa[N];
int n, m;
void init(int n) {
  for (int i = 1; i <= n; i++) {
    fa[i] = i;
  }
}
 
int find(int x) {
  if (x == fa[x])
    return x;
  else
    return fa[x] = find(fa[x]);
}
 
void merge(int x, int y) {
  fa[find(x)] = find(y);
}
 
void solve(int x) {
  init(n + 10);
 
  for (int i = 1; i <= m; i++) {
    int a, b;
    cin >> a >> b;
    merge(a, b);
  }
 
  int num = 0;
  for (int i = 1; i <= n; i++) {
    if (fa[i] == i) {
      num++;
    }
  }
  cout << "Case " << x << ": "  << num << endl;
}
 
int main() {
  int x = 1;
  while (cin >> n >> m) {
    if (n == 0 && m == 0)
      break;
    solve(x++);
  }
  return 0;
}