HDU1213 How Many Tables（简单的并查集）

#include <iostream>
#include <string>
using namespace std;
int father[1010],a,b,visit[1010];
int find(int x)
{
if(x!=father[x])
father[x]=find(father[x]);
return father[x];
}
void mere(int x,int y)
{
x=find(x);
y=find(y);
father[y]=x;
}
int main()
{
int i,m,n,t,j,a,b;
cin>>t;
while(t--)
{
int count=0;
memset(visit,0,sizeof(visit));
cin>>n>>m;
for(i=1;i<=n;i++)
father[i]=i;
for(i=1;i<=m;i++)
{
cin>>a>>b;
a=find(a);
b=find(b);
if(a!=b)
mere(a,b);
}
for(i=1;i<=n;i++)
{
if(visit[i])
continue;
//    visit[i]=1;
for(j=i+1;j<=n;j++)
{
if(!visit[j]&&find(i)==find(j))
{
visit[j]=1;
}
}
count++;
}
cout<<count<<endl;
}
return 0;
}