#include <stdio.h>
#include <stdlib.h>
#define N 200050
#define M (1 << 24)
int n, x[N], y[N], t[N * 2], ll[N],
A[M], L[M], R[M], ii,
up[N],
vv_[99], ll_[99], rr_[99], ii_;
long long ans;
void add(int *v, int l, int r, int p, int k)
{
if (!*v)
{
*v = ++ii;
A[*v] = L[*v] = R[*v] = 0;
}
A[*v] += k;
if (l == r)
return;
if (p <= (l + r) / 2)
add(L + *v, l, (l + r) / 2, p, k);
else
add(R + *v, (l + r) / 2 + 1, r, p, k);
}
int sum(int v, int l, int r, int x, int y)
{
if (!v || r < x || y < l)
return 0;
if (x <= l && r <= y)
return A[v];
return sum(L[v], l, (l + r) / 2, x, y) + sum(R[v], (l + r) / 2 + 1, r, x, y);
}
void generate(int v, int l, int r, int x, int y)
{
if (!v || r < x || y < l)
return;
if (x <= l && r <= y)
{
vv_[ii_] = v;
ll_[ii_] = l;
rr_[ii_] = r;
++ii_;
return;
}
generate(L[v], l, (l + r) / 2, x, y);
generate(R[v], (l + r) / 2 + 1, r, x, y);
}
int next_(int v, int l, int r, int x, int y)
{
if (l == r)
return l;
if (A[L[v]])
return next_(L[v], l, (l + r) / 2, x, y);
return next_(R[v], (l + r) / 2 + 1, r, x, y);
}
int next(int v, int l, int r, int x, int y)
{
int i;
ii_ = 0;
generate(v, l, r, x, y);
for (i = 0; i < ii_; ++i)
if (A[vv_[i]])
return next_(vv_[i], ll_[i], rr_[i], x, y);
return r;
}
int cx(const void *i, const void *j)
{
return x[*(int*)i] - x[*(int*)j];
}
int cy(const void *i, const void *j)
{
return - y[*(int*)i] + y[*(int*)j];
}
void pus(int **eh, int *eo, int x)
{
int o;
o = eo[0]++;
if (!o)
eh[0] = malloc(2 * sizeof **eh);
else if (0 == (o & (o - 1)))
eh[0] = realloc(eh[0], o * 2 * sizeof **eh);
eh[0][o] = x;
}
void dnc(int l, int r, int *ll, int lo)
{
int *aa, ao, *bb, bo, *cc, co
, i, j, m, *aa_, ao_, *bb_, bo_
, t1, t2;
if (!lo || l > r)
return;
ao = 0;
bo = 0;
co = 0;
ao_ = 0;
bo_ = 0;
aa_ = 0;
bb_ = 0;
aa = 0;
bb = 0;
cc = 0;
t1 = 0;
t2 = 0;
m = (l + r) / 2;
for (i = 0; i < lo; ++i)
{
if (x[ll[i]] <= m)
{
pus(&aa, &ao, ll[i]);
pus(&aa_, &ao_, ll[i]);
}
else if (x[ll[i]] > m)
{
pus(&bb, &bo, ll[i]);
pus(&bb_, &bo_, ll[i]);
}
}
for (i = ao - 1; i >= 0; --i)
{
up[aa[i]] = next(t1, 0, 1e9, y[aa[i]] + 1, 1e9);
add(&t1, 0, 1e9, y[aa[i]], 1);
}
ii = 0;
qsort(aa_, ao_, sizeof *aa_, cy);
qsort(bb_, bo_, sizeof *bb_, cy);
j = 0;
for (i = 0; i < ao; ++i)
{
while (j < bo_ && y[bb_[j]] > y[aa_[i]])
{
while (co && x[cc[co - 1]] > x[bb_[j]])
{
add(&t2, 0, 1e9, y[cc[co - 1]], -1);
--co;
}
pus(&cc, &co, bb_[j]);
add(&t2, 0, 1e9, y[cc[co - 1]], 1);
++j;
}
ans += sum(t2, 0, 1e9, y[aa_[i]], up[aa_[i]]);
}
ii = 0;
free(cc);
free(aa_);
free(bb_);
if (l < r)
{
dnc(l, m, aa, ao);
dnc(m + 1, r, bb, bo);
}
free(aa);
free(bb);
}
int main()
{
int i;
scanf("%d", &n);
x[n] = 2e9;
for (i = 0; i < n; ++i)
{
scanf("%d%d", x + i, y + i);
ll[i] = i;
}
qsort(ll, n, sizeof *ll, cx);
dnc(0, 1e9, ll, n);
printf("%lld", ans);
return 0;
}
