How Many Tables浅析

How Many Tables：
这道题考察的是我们的并查集：
只需要将有联系的人的根节点连在一起就可以很轻松的写出程序。
代码如下：

#include <iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int father[2020];
int number;
int f(int root)
{
    
    
    int son, tmp;
	son = root;
	while(root != father[root])
		root = father[root];
	while(son != root)
	{
    
    
		tmp = father[son];
		father[son] = root;
		son = tmp;
	}
	return root;
}
void hebing(int x,int y)
{
    
    
    int fatherx;
    int fathery;
    fatherx=f(x);//获取根节点
    fathery=f(y);//获取根节点
    if(fatherx<fathery)
    {
    
    
        father[fathery]=fatherx;
        number--;
    }
    if(fathery<fatherx)
    {
    
    
        father[fatherx]=fathery;
        number--;
    }
}
int main()
{
    
    
    int t;
    int n,m;
    int a1,a2;
    cin>>t;
    while(t--)
    {
    
    
        cin>>n>>m;
        number=n;
        for(int i=1;i<=n;i++)
            father[i]=i;
        for(int j=0;j<m;j++)
        {
    
    
            cin>>a1>>a2;
            hebing(a1,a2);
        }
        cout<<number<<endl;
    }
    return 0;
}