#include <bits/stdc++.h>
using namespace std;
int main(){
int t;
cin>>t;
vector<pair<long long,long long>> inp(t+1);
vector<pair<long long,int>> mape(t+1);
long long sum=0;

for(int i=1;i<=t;i++){
cin>>inp[i].first>>inp[i].second;
mape[i].first=inp[i].second-inp[i].first;
mape[i].second=i;
sum+=inp[i].second;
}

sum=sum*t;
sort(mape.begin()+1,mape.end());

for(int j=1;j<=t;j++){
    sum+=inp[mape[j].second].first*(j-1);
    sum-=inp[mape[j].second].second*j;
}

cout<<sum;
}