#include<bits/stdc++.h>
using namespace std;
using LL = long long;
const int NBunhin = (int)2e5 + 5, inf = (int)1e9 + 123;
int nBunhin;
vector<int> compX, compY;
LL ans;
struct Bunhin {
int x, y;
Bunhin(int _x = 0, int _y = 0) : x(_x), y(_y) {}
bool operator<(const Bunhin &_) const { return x < _.x; }
} bunhin[NBunhin];
struct Bit {
int num[NBunhin];
Bit() { memset(num, 0, sizeof num); }
void upd(int pos, int val) {
for (; pos < NBunhin; pos += pos & -pos) num[pos] += val;
}
int get(int pos) {
int ret = 0;
for (; pos > 0; pos -= pos & -pos) ret += num[pos];
return ret;
}
} bit;
int compXId(int val) {
return (int)(lower_bound(compX.begin(), compX.end(), val) - compX.begin() ) + 1;
}
int compYId(int val) {
return (int)(lower_bound(compY.begin(), compY.end(), val) - compY.begin() ) + 1;
}
void solve(int Left, int Right) {
if (Right - Left < 2) {
if (bunhin[Left].x < bunhin[Right].x && bunhin[Left].y < bunhin[Right].y) ++ans;
return ;
}
int Mid = (Left + Right) >> 1;
solve(Left, Mid); solve(Mid, Right);
vector< pair<int, int> > rightInterval;
vector< array<int, 3> > leftInterval;
set<int> ySet;
for (int i = Mid + 1; i <= Right; ++i) {
ySet.emplace(bunhin[i - 1].y);
set<int>::iterator it = ySet.lower_bound(bunhin[i].y);
if (it == ySet.begin() ) rightInterval.emplace_back(compYId(-inf), bunhin[i].y);
else rightInterval.emplace_back(*(--it), bunhin[i].y);
}
sort(rightInterval.begin(), rightInterval.end(), [&](pair<int, int> a, pair<int, int> b) { return a.second < b.second; } );
ySet.clear();
for (int i = Mid - 1; i >= Left; --i) {
ySet.emplace(bunhin[i + 1].y);
set<int>::iterator it = ySet.upper_bound(bunhin[i].y);
if (it == ySet.end() ) {
leftInterval.emplace_back(array<int, 3>{ bunhin[i].y, bunhin[i].y, 1 } );
leftInterval.emplace_back(array<int, 3>{ compYId(inf), bunhin[i].y, -1 } );
}
else {
leftInterval.emplace_back(array<int, 3>{ bunhin[i].y, bunhin[i].y, 1 } );
leftInterval.emplace_back(array<int, 3>{ (*it) + 1, bunhin[i].y, -1 } );
}
}
sort(leftInterval.begin(), leftInterval.end() );
int iLeftInterval = 0;
for (auto rInterval : rightInterval) {
while (iLeftInterval < (int)leftInterval.size() && leftInterval[iLeftInterval][0] <= rInterval.second) {
bit.upd(leftInterval[iLeftInterval][1], leftInterval[iLeftInterval][2]);
++iLeftInterval;
}
ans += bit.get(rInterval.second) - bit.get(rInterval.first - 1);
}
while (iLeftInterval < (int)leftInterval.size() ) {
bit.upd(leftInterval[iLeftInterval][1], leftInterval[iLeftInterval][2]);
++iLeftInterval;
}
}
int main() {
// freopen("input", "r", stdin);
scanf(" %d", &nBunhin);
for (int i = 1; i <= nBunhin; ++i) {
int x, y; scanf(" %d %d", &x, &y);
bunhin[i] = Bunhin(x, y);
compX.emplace_back(x);
compY.emplace_back(y);
}
compX.emplace_back(-inf); compX.emplace_back(inf);
compY.emplace_back(-inf); compY.emplace_back(inf);
sort(compX.begin(), compX.end() );
sort(compY.begin(), compY.end() );
for (int i = 1; i <= nBunhin; ++i) {
bunhin[i].x = compXId(bunhin[i].x);
bunhin[i].y = compYId(bunhin[i].y);
}
sort(bunhin + 1, bunhin + nBunhin + 1);
solve(1, nBunhin);
printf("%lld\n", ans);
return 0;
}
