poj 2492 A Bug's Life (并查集)

题目：http://poj.org/problem?id=2492

题意：跟上一道1703题差不做，

给出m对昆虫交配，问 有没有同性恋。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
using namespace std;
const int maxn = 2010;
int bin[maxn], op[maxn], n;
void init()
{
    for(int i = 1; i <= n; i++)
    {
        bin[i] = i;
        op[i] = 0;
    }
}
int find(int x)
{
    int r, i, j;
    r =  x;
    while(r != bin[r])
        r = bin[r];
    i = x;
    while(bin[i] != r)
    {
        j = bin[i];
        bin[i] = r;
        i = j;
    }
    return r;
}

void merge(int x, int y)
{
    int fx, fy;
    fx = find(x);
    fy = find(y);
    if(fx != fy)
        bin[fx] = fy;
}
int main()
{
    int t, m, a, b, f, cou=1;
    scanf("%d", &t);
    while(t--)
    {
        f = 0;
        scanf("%d%d", &n, &m);
        init();

        while(m--)
        {
            scanf("%d%d",&a, &b);
            if(find(a) == find(b))
                f = 1;
            if(f == 0)
            {
                if(op[a] == 0)
                    op[a] = b;
                else
                    merge(op[a],b);
                if(op[b] == 0)
                    op[b] =a;
                else
                    merge(op[b],a);
            }
        }
        printf("Scenario #%d:\n", cou++);
        if(f)
            printf("Suspicious bugs found!\n\n");
        else
            printf("No suspicious bugs found!\n\n");
    }
    return 0;
}