#include <iostream>

#include <algorithm>

#include <cstdio>

#define REP(i,a,n) for(int i=a;i<=n;++i)

using namespace std;

typedef long long ll;

const int N = 1e6+10, INF = 0x3f3f3f3f;

int n, c[N], vis[N], b[N];

struct _ {

	int x,y;

	bool operator < (const _&rhs) const {

		if (y!=rhs.y) return y>rhs.y;

		return x<rhs.x;

	}

} a[N];

int ID(int x) {

	return lower_bound(b+1,b+1+*b,x)-b;

}

int qry(int x) {

	int r = 0;

	for (; x; x^=x&-x) r+=c[x];

	return r;

}

int qry(int l, int r) {

	return qry(ID(r))-qry(ID(l-1));

}

void add(int x) {

	x = ID(x);

	if (!vis[x]) {

		vis[x] = 1;

		for (; x<=*b; x+=x&-x) ++c[x];

	}

}

int main() {

	scanf("%d", &n);

	REP(i,1,n) {

		scanf("%d%d",&a[i].x,&a[i].y);

		b[++*b]=a[i].x;

		b[++*b]=a[i].x-1;

	}

	b[++*b]=0,b[++*b]=INF;

	sort(b+1,b+1+*b),*b=unique(b+1,b+1+*b)-b-1;

	sort(a+1,a+1+n);

	ll ans = 0;

	REP(i,1,n) {

		int j=i;

		while (j<n&&a[j+1].y==a[i].y) ++j;

		REP(k,i,j) {

			int L = qry(1,a[k].x-1);

			int R = qry(a[k].x+1,k==j?INF:a[k+1].x-1);

			ans += (ll)(L+1)*(R+1);

			add(a[k].x);

		}

		i = j;

	}

	printf("%lld\n", ans);

}