poj union_find相关之1611 The Suspects

poj union-find 1611 The Suspects
就是简单的并查集

#include<cstdio>#include<cstring>#include<iostream>#include<memory.h>#define MAXS 30005#define MAXG 505using namespace std;int n, m;int pre[MAXS];int find(int t){    int a = t;    while (pre[a] != a)        a = pre[a];    return a;}void union_int(int a,int b){    int x, y;    x = find(a);    y = find(b);    if (x != y)        pre[y] = x;}int main(){    //freopen("1.txt", "r", stdin);    int i, j, k, a, b, cont;    while (scanf("%d%d", &n, &m) != EOF && (n || m))    {        for (i = 0; i < n; i++)            pre[i] = i;        for (i = 0; i < m; i++)        {            scanf("%d", &k);            scanf("%d", &a);            for (j = 1; j < k; j++)            {                scanf("%d", &b);                union_int(a, b);            }        }        cont = 1;        j = find(0);        for (i = 1; i < n;i++)        if (find(i) == j)            cont++;        printf("%d\n", cont);    }}

252K 16MS

比较高端的并查集的题 1182:食物链可以参考如下的博客：
http://blog.163.com/happyliyifan@126/blog/static/37462772201361695127793/
http://blog.csdn.net/tiantangrenjian/article/details/7085575