#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
const int N = 3e5 + 10;
int n, x[N], y[N];
vector <int> X, Y;
void compress(vector <int> &v) {
sort(v.begin(), v.end());
v.erase(unique(v.begin(), v.end()), v.end());
}
int id(vector <int> &v, int val) {
return lower_bound(v.begin(), v.end(), val) - v.begin();
}
int cntX[N], cntY[N];
int main() {
cin.tie(0); cout.tie(0);
ios_base::sync_with_stdio(false);
cin >> n;
for (int i = 1; i <= n; ++i) {
cin >> x[i] >> y[i];
X.push_back(x[i]);
Y.push_back(y[i]);
}
compress(X);
compress(Y);
for (int i = 1; i <= n; ++i) {
x[i] = id(X, x[i]);
y[i] = id(Y, y[i]);
++cntX[x[i]];
++cntY[Y[i]];
}
long long ans = 0;
for (int i = 1; i <= n; ++i) {
ans += 1ll * (cntX[x[i]] - 1) * (cntY[y[i]] - 1);
}
cout << ans << "\n";
return 0;
}
