UVALive X-Plosives（并查集+略坑的输入）

1.此题的题意非常简单，但是题目可能较难读懂

2.输入输出是坑，输入-1后再输入eof文件才结束，且

3.此题的代码如下：

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <queue>
#include <cmath>
using namespace std;
int fat[100100];
int Find(int a)
{
    while(fat[a]!=a)
        a = fat[a];
    return a;
}
void join(int a,int b)
{
    int fx=Find(a),fy=Find(b);
    if(fx!=fy)
        fat[fx]=fy;
}
void init()
{
    for(int i=1;i<=100050;i++)
        fat[i]=i;
}
int main()
{
    int num1,num2,ans=0;
    while(~scanf("%d%d",&num1,&num2))
    {
        ans=0;
        init();
        join(num1,num2);
        while(scanf("%d",&num1),num1!=-1)
        {
            scanf("%d",&num2);
            if(Find(num1)!=Find(num2))
            {
                join(num1,num2);
            }
            else
            {
                //cout<<num1<<num2<<endl;
                ans++;
            }
        }
        printf("%d\n",ans);
    }

    return 0;
}