#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
int main() {
	// your code goes here
	int n;
	cin>>n;
	ll sum = 0;
	vector<ll> p;
	for(int i = 0 ; i< n ; i++){
		int a , b;
		cin>>a>>b;
		sum += b*n - a;
		p.push_back(b-a);
	}
	sort(p.begin(),p.end());
	reverse(p.begin(),p.end());
	for(int j = 1; j<= n ; j++){
		sum = sum + j*p[j-1];
	}
	cout<<sum<<endl;
	return 0;
}