POJ 2492 并查集应用的扩展

TUD Programming Contest 2005, Darmstadt, Germany

/*********************************
     author   : Grant Yuan
     time     : 2014/10/5 11:29
     algorithm: 并查集应用的扩展
     source   : POJ 2492
**********************************/
#include<iostream>
#include<cstdio>
#define MAX 2007
using namespace std;
int parent[MAX],relation[MAX];
int n,t,m;
int find_parent(int k)
{
    if(k==parent[k])
        return k;
    int t=parent[k];
    parent[k]=find_parent(parent[k]);
    relation[k]=(relation[k]+relation[t]+1)%2;
    return parent[k];
}
void unite(int a,int b)
{
    int pa=find_parent(a);
    int pb=find_parent(b);
    parent[pa]=pb;
    relation[pa]=(relation[b]-relation[a])%2;
}
int main()
{
    scanf("%d",&t);
    int ct=1;bool first=0;
    while(t--){
        bool ans=0;
        scanf("%d%d",&n,&m);
        for(int i=1;i<=n;i++)
            parent[i]=i,relation[i]=1;
        for(int i=1;i<=m;i++)
        {
            int a,b;
            scanf("%d%d",&a,&b);
            int pa=find_parent(a);
            int pb=find_parent(b);
            if(pa==pb){
                if(relation[a]==relation[b]) ans=1;
            }
            else unite(a,b);
        }
        printf("Scenario #%d:\n",ct++);
        if(ans) printf("Suspicious bugs found!\n\n");
        else printf("No suspicious bugs found!\n\n");
    }
    return 0;
}

POJ 2492 并查集应用的扩展

原文：http://blog.csdn.net/yuanchang_best/article/details/39802103