#include <bits/stdc++.h>
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
using ll = long long;
const ll mod = 998244353;
#define fi first
#define se second
#define rep(i,n) for(ll i=0;i<n;i++)
#define all(x) x.begin(),x.end()
#define faster ios::sync_with_stdio(false);cin.tie(nullptr)
int main() {
ll N;
cin >> N;
vector<ll> X(N),Y(N);
rep(i,N) cin >> X[i] >> Y[i];
vector<ll> x=X,y=Y;
sort(all(x));
x.erase(unique(all(x)),x.end());
sort(all(y));
y.erase(unique(all(y)),y.end());
rep(i,N) X[i]=lower_bound(all(x),X[i])-x.begin();
rep(i,N) Y[i]=lower_bound(all(y),Y[i])-y.begin();
vector<ll> cntX(300500,0),cntY(300500,0);
rep(i,N) cntX[X[i]]++;
rep(i,N) cntY[Y[i]]++;
ll ans=0;
rep(i,N){
ans+=(cntX[X[i]]-1)*(cntY[Y[i]]-1);
}
cout << ans << endl;
return 0;
}
