RT，全MLE求助，空间哪里开大了

#include<bits/stdc++.h>
using namespace std;
int fa[1005];
inline int getfa(int x){
	if(fa[x]==x)return x;
	return fa[x]=getfa(fa[x]);
}
bool st[1005];
int n,m,cnt=0,x,y;
signed main(){
	while(1){
		cin>>n;if(n==0)break;cin>>m;
		cnt=0;
		memset(st,0,sizeof(st));
		for(int i=1;i<=n;++i)fa[i]=i;
		for(int i=1;i<=m;++i)
			cin>>x,cin>>y,fa[getfa(x)]=y;
		for(int i=1;i<=n;++i)st[getfa(i)]=1;
		for(int i=1;i<=n;++i)cnt+=st[i];
		cout<<cnt-1<<'\n';
	}
	puts("");
	return 0;
}
//sto AC orz