#include <bits/stdc++.h>
using namespace std;
bool comp(pair<long long, long long> a, pair<long long, long long> b) {
  if (a.first > a.second && a.first > b.first) return 1;
  return 0;
}
void solve() {
  long long n;
  cin >> n;
  vector<pair<double, pair<long long, long long>>> v(n);
  for (long long i = (0); i < (n); ++i) {
    cin >> v[i].second.first >> v[i].second.second;
    v[i].first = v[i].second.first - v[i].second.second;
  }
  sort(v.begin(), v.end());
  reverse(v.begin(), v.end());
  long long s = 0;
  for (long long i = (0); i < (n); ++i) {
    s += v[i].second.first * i + v[i].second.second * (n - i - 1);
  }
  cout << s;
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long t1 = 1;
  while (t1--) {
    solve();
    cout << "\n";
    ;
  }
}
