#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define f first
#define s second
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pb push_back
#define epb emplace_back
using namespace std;
const int nmax = 200005;
vector <pii> points;
vector <int> t(4 * nmax);
void upd(int v, int l, int r, int pos, int val){
if(l > pos || r < pos){
return;
}
if(l == r){
t[v] = val;
return;
}
int m = (l + r) / 2;
upd(2 * v, l, m, pos, val);
upd(2 * v + 1, m + 1, r, pos, val);
t[v] = t[2 * v] + t[2 * v + 1];
}
int get(int v, int l, int r, int st, int fin){
if(l > fin || r < st){
return 0;
}
if(l >= st && r <= fin)
return t[v];
int m = (l + r) / 2;
return get(2 * v, l,m, st, fin) + get(2 * v + 1, m + 1, r, st, fin);
}
int cur[nmax];
ll ans = 0;
void divi(int l, int r){
if(l >= r)
return;
int m = (l + r) / 2;
set <pii> st;
vector <pii> vec;
vector <pair<pii, int> > vv;
for(int i = l; i <= m; i++){
vv.pb({{points[i].s, points[i].f}, i});
}
sort(vv.begin(), vv.end());
reverse(vv.begin(), vv.end());
stack <int> s;
s.push(vv[0].s);
cur[vv[0].s] = 200001;
for(int i = 1; i < vv.size(); i++){
while(!s.empty()){
int v = s.top();
if(points[v].f > points[vv[i].s].f){
break;
}
else s.pop();
}
if(s.empty()){
cur[vv[i].s] = 200001;
}
else cur[vv[i].s] = points[s.top()].s;
s.push(vv[i].s);
}
for(int i= l; i <= r; i++){
vec.epb(points[i].s, i);
}
sort(vec.begin(), vec.end());
reverse(vec.begin(), vec.end());
for(int i= 0; i < vec.size(); i++){
if(vec[i].s <= m){
int xx = cur[vec[i].s];
int o = vec[i].s;
ans += (ll)get(1, 1, 200001, points[o].s, xx);
//upd(1, 1, 200000, points[i].s, 1);
}
else{
int o = vec[i].s;
auto it = st.upper_bound({points[o].f, -1});
vector <pii> er;
while(it != st.end()){
er.pb(*it);
it++;
}
for(auto to : er){
int x= to.s;
upd(1, 1, 200001, points[x].s, 0);
st.erase(to);
}
st.insert({points[o].f, o});
upd(1, 1, 200001, points[o].s, 1);
}
}
st.clear();
for(int i = l; i <= r; ++i){
cur[points[i].s] = 0;
upd(1, 1, 200001, points[i].s, 0);
}
//cout << ans << "\n";
divi(l, m);
divi(m + 1, r);
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0);
int n; cin >> n;
int x[n + 1];
int y[n + 1];
map <int, int> mpx, mpy;
vector <int> xx, yy;
for(int i= 1; i<= n ;++i){
cin >> x[i] >> y[i];
xx.pb(x[i]);
yy.pb(y[i]);
}
sort(xx.begin(), xx.end());
sort(yy.begin(), yy.end());
for(int i = 0; i < xx.size(); i++){
mpx[xx[i]] = i + 1;
}
for(int i = 0; i < yy.size(); i++){
mpy[yy[i]] = i + 1;
}
for(int i = 1; i <= n; i++){
points.pb({mpx[x[i]], mpy[y[i]]});
}
sort(points.begin(), points.end());
divi(0, n - 1);
cout << ans;
}
