哦。

#include <bits/stdc++.h>
using namespace std;
int a[1000001];
int n,m,p;
int find(int x)
{
	if(x==a[x])	return x;
	
	else return a[x]=find(a[x]);
}
void join(int x,int y)
{
	int xx = find(x);
	int yy = find(y);
	if(xx != yy)
	{
		a[xx]=yy;
	}
}
int main()
{
	cin>>n>>m>>p;
	for(int i=1;i<=n;i++)	a[i]=i;
	
	for(int i=1;i<=m;i++)
	{
		int x,y;
		cin>>x>>y;
		join(x,y);
	}
	for(int i=1;i<=p;i++)
	{
		int x,y;
		cin>>x>>y;
		if(find(x)==find(y))
		{
			cout<<"Yes"<<endl;
		}
		else
		{
			cout<<"No"<<endl;
		}
	}
	return 0;

}