#include<bits/stdc++.h>
using namespace std;

void solve(){
    int n;cin>>n;
    vector<int>a(n),b(n),diff(n);
    long long c=0;
    for(int i=0;i<n;i++){
        cin>>a[i]>>b[i];
        c+=(long long)b[i]*n-a[i];
        diff[i]=a[i]-b[i];
    }
    sort(diff.begin(),diff.end());
    for(int j=n-1;j>=0;j--){
        c+=(long long)diff[j]*(n-j);
    }

    cout<<c<<endl;
}

int main(){
    solve();
}