并查集的简单使用 pku 1611 The Suspects

题目链接:

http://acm.pku.edu.cn/JudgeOnline/problem?id=1611

 

#include <stdio.h>#define MAX_STUDENT 30000int parent[MAX_STUDENT];int num[MAX_STUDENT];void make_set(int x){parent[x] = x;num[x] = 1;}int find_set(int x){if(x != parent[x])parent[x] = find_set(parent[x]);return parent[x];}void union_set(int x,int y){x = find_set(x);y = find_set(y);if(x == y)return;if(num[x] <= num[y]){parent[x] = y;num[y] += num[x];}else{parent[y] = x;num[x] += num[y];}}int main(){int n,m;int k,first,member;int i,j;while(scanf("%d%d",&n,&m)){if(n == 0 && m == 0)break;for(i = 0;i < n;i++)make_set(i);for(j = 0;j < m;j++){scanf("%d%d",&k,&first);for(i = 0;i < k - 1;i++){scanf("%d",&member);union_set(first,member);}}printf("%d/n",num[find_set(0)]);}return 0;}