#include<bits/stdc++.h>
#define For(a,b,c) for(int a=b;a<=c;++a)
#define Dor(a,b,c) for(int a=b;a>=c;--a)
using namespace std;
const int N=300300;
int n,C[N],S[N],X[N],Y[N];
int Find(int u) {
	return u==C[u]?u:C[u]=Find(C[u]);
}
void Uni(int x,int y) {
	x=Find(x),y=Find(y);
	if(x!=y) C[x]=y,S[y]+=S[x],X[y]+=X[x],Y[y]+=Y[x];
}
int main() {
	scanf("%d",&n);
	For(i,1,300020) C[i]=i;
	For(i,1,100000) X[i+100010]=1;
	For(i,1,100000) Y[i+200020]=1;
	For(i,1,n) S[i]=1;
	For(i,1,n) {
		int x,y;
		scanf("%d%d",&x,&y);
		Uni(i,x+100010);
		Uni(i,y+200020);
	}
	long long ans=0;
	For(i,1,300020)
	if(i==Find(i)) {
		int x=X[i],y=Y[i],s=S[i];
		ans+=1LL*x*y-s;
	}
	printf("%lld",ans);
	return 0;
}