hdu 1213 How Many Tables（并查集练习）

#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<queue>
#define MAXN 10
using namespace std;
int father[1005];
void build(int n)
{
for(int i = 0 ; i <= n ; i ++)
father[i] = i;
}
int find(int x)
{
if(x != father[x])
{
father[x] = find(father[x]);
}
return father[x];
}
void Union(int x,int y)
{
x = find(x);
y = find(y);
if(x == y) return;
father[y] = x;
}
int main()
{
int T,n,m,i,x,y;
scanf("%d",&T);
while(T--)
{
scanf("%d%d",&n,&m);
build(n);
while(m--)
{
scanf("%d%d",&x,&y);
Union(x,y);
}
int ans = 0;
for(i = 1 ; i <= n ; i ++)
if(father[i] == i) ans ++;
printf("%d\n",ans);
}
return 0;
}