#include <bits/stdc++.h>
using namespace std;
#define int long long
#define eb emplace_back
#define mp make_pair
#define pb push_back
#define pp pop_back
#define endl '\n'
#define ff first
#define ss second
#define stop exit(0)
#define sz(x) (int)x.size()
#define pause system("pause")
#define all(x) (x).begin(), (x).end()
#define deb(x) cout << #x << "-" << x << endl
typedef char chr;
typedef string str;
typedef long long ll;
typedef vector<int> vii;
typedef pair<int, int> pii;
const long long INF = LLONG_MAX;
const int inf = INT_MAX;
const int mod = 998244353;
const int MOD = 1e9 + 7;
const int dx[] = {0, 0, -1, 1};
const int dy[] = {-1, 1, 0, 0};
const double PI = 2 * acos(0.0);
const int N = 3e5 + 5;
int n;
int x[N],y[N];
map <int,int> X,Y;
int ans;
inline void test_case() {
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> x[i] >> y[i];
X[x[i]+N]++;
Y[y[i]+N]++;
}
for (int i = 1; i <= n; i++) {
ans += (X[x[i]+N]-1)*(Y[y[i]+N]-1);
}
cout << ans << endl;
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
int T = 1;
// cin >> T;
while (T--) {
test_case();
}
return 0;
}
