#include <bits/stdc++.h>
#define ll long long
#define f first
#define s second
using namespace std;
const int maxn=2e5+5;
int n;
int x[maxn],y[maxn];
vector<int> nen;
vector<vector<int>> a,sum;
int get(int i,int j,int u,int v)
{
return sum[u][v]-sum[i-1][v]-sum[u][j-1]+sum[i-1][j-1];
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
cin>>n;
for(int i=1;i<=n;i++){
cin>>x[i]>>y[i];
nen.push_back(x[i]);
nen.push_back(y[i]);
}
sort(nen.begin(),nen.end());
nen.erase(unique(nen.begin(),nen.end()),nen.end());
int maxX=0,maxY=0;
for(int i=1;i<=n;i++){
x[i]=lower_bound(nen.begin(),nen.end(),x[i])-nen.begin()+1;
y[i]=lower_bound(nen.begin(),nen.end(),y[i])-nen.begin()+1;
maxX=max(maxX,x[i]);
maxY=max(maxY,y[i]);
}
a.assign(maxX+1,vector<int>(maxY+1,0));
sum.assign(maxX+1,vector<int>(maxY+1,0));
for(int i=1;i<=n;i++){
a[x[i]][y[i]]=1;
}
for(int i=1;i<=maxX;i++){
for(int j=1;j<=maxY;j++){
sum[i][j]=sum[i-1][j]+sum[i][j-1]-sum[i-1][j-1]+a[i][j];
}
}
ll ans=0;
for(int i=1;i<=maxX;i++){
for(int j=1;j<=maxY;j++){
if(a[i][j]==1){
int right=0,left=0,up=0,down=0;
if(j+1<=maxY) right=get(i,j+1,i,maxY);
if(j-1>=1) left=get(i,1,i,j-1);
if(i-1>=1) up=get(1,j,i-1,j);
if(i+1<=maxX) down=get(i+1,j,maxX,j);
ans+=1LL*right*down;
ans+=1LL*down*left;
ans+=1LL*left*up;
ans+=1LL*up*right;
}
}
}
cout<<ans;
}
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