#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define rep(i,a,b) for(int i=a; i<=b; i++)
const int N = 300005;
int x[N], y[N];
vector<int> vecx, vecy;
map<int, int> comp;
int cntX[N], cntY[N];
signed main() {
int n;
cin >> n;
rep(i, 1, n) {
int u, v;
cin >> u >> v;
x[i] = u;
y[i] = v;
vecx.pb(u);
vecy.pb(v);
}
int idx = 1;
sort(vecx.begin(), vecx.end());
for (int i = 0; i < vecx.size(); i++) {
if (comp.count(vecx[i]) == 0)
comp[vecx[i]] = idx++;
}
sort(vecy.begin(), vecy.end());
for (int i = 0; i < vecy.size(); i++) {
if (comp.count(vecy[i]) == 0)
comp[vecy[i]] = idx++;
}
rep(i, 1, n) {
int cx = comp[x[i]];
int cy = comp[y[i]];
cntX[cx]++;
cntY[cy]++;
}
int ans = 0;
rep(i, 1, n) {
int cx = comp[x[i]];
int cy = comp[y[i]];
ans += (cntX[cx] - 1) * (cntY[cy] - 1);
}
cout << ans << "\n";
}
