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

int main() {
	long long n;
	cin>>n;
	long long answer=0;
	vector<long long> arr1;
	vector<long long> arr2;
	long long constantPart=0;
	for(long long i=0;i<n;i++){
		long long a,b;
		cin>>a>>b;
		arr1.push_back(a-b);
		constantPart+=b*n-a;
	}
	sort(arr1.begin(), arr1.end());
	for(int i=1;i<=n;i++)
		arr2.push_back(i);
	reverse(arr2.begin(), arr2.end());
	for(int i=0;i<n;i++){
		answer+=arr1[i]*arr2[i];	
	}
	answer+=constantPart;
	cout<<answer;
	return 0;
}