poj2492 A Bug's Life（并查集）

题意：有n个虫子，人们认为只有性别不同的时候才会发生性关系，现在给出m组虫子发生了关系，问是否存在同性恋（这题目...真变态）

思路：并查集，将性别相同的划分在一个集合，不同的划分在另一个

#include <cstdio>#include <queue>#include <cstring>#include <iostream>#include <cstdlib>#include <algorithm>#include <vector>#include <map>#include <string>#include <set>#include <ctime>#include <cmath>#include <cctype>using namespace std;#define maxn 2010#define LL long longint cas=1,T;int pre[maxn];int resex[maxn];int rank[maxn];int n;void init(){for (int i = 1;i<=n;i++){pre[i]=i;resex[i]=0;rank[i]=0;}}int Find(int x){int r = x;while (r!=pre[r])r=pre[r];int i = x,j;while (pre[i]!=r){j = pre[i];pre[i]=r;i=j;}return r;}void mix(int x,int y){int fx = Find(x),fy=Find(y);/*if (rank[fx] > rank[fy])pre[fy]=fx;else{pre[fx]=fy;if (rank[x]==rank[y])rank[y]++;}*/if (fx!=fy)pre[fx]=fy;}int main(){//freopen("in","r",stdin);scanf("%d",&T);while (T--){int flag = 1;int m;scanf("%d%d",&n,&m);init();for (int i = 1;i<=m;i++){int a,b;scanf("%d%d",&a,&b);if (!flag)continue;int x = Find(a);int y = Find(b);if (x==y)flag = 0;if (resex[a]!=0)mix(resex[a],b);elseresex[a]=b;if (resex[b]!=0)mix(resex[b],a);elseresex[b]=a;}printf("Scenario #%d:\n",cas++);if (!flag)printf("Suspicious bugs found!\n\n");elseprintf("No suspicious bugs found!\n\n");}//printf("time=%.3lf",(double)clock()/CLOCKS_PER_SEC);return 0;}

题目

Description

Background
Professor Hopper is researching the sexual behavior of a rare species of bugs. He assumes that they feature two different genders and that they only interact with bugs of the opposite gender. In his experiment, individual bugs and their interactions were easy to identify, because numbers were printed on their backs. 
Problem
Given a list of bug interactions, decide whether the experiment supports his assumption of two genders with no homosexual bugs or if it contains some bug interactions that falsify it.

Input

The first line of the input contains the number of scenarios. Each scenario starts with one line giving the number of bugs (at least one, and up to 2000) and the number of interactions (up to 1000000) separated by a single space. In the following lines, each interaction is given in the form of two distinct bug numbers separated by a single space. Bugs are numbered consecutively starting from one.

Output

The output for every scenario is a line containing "Scenario #i:", where i is the number of the scenario starting at 1, followed by one line saying either "No suspicious bugs found!" if the experiment is consistent with his assumption about the bugs' sexual behavior, or "Suspicious bugs found!" if Professor Hopper's assumption is definitely wrong.

Sample Input

23 31 22 31 34 21 23 4

Sample Output

Scenario #1:Suspicious bugs found!Scenario #2:No suspicious bugs found!

Hint

Huge input,scanf is recommended.