#include <bits/stdc++.h>
using namespace std;
void file() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
}
void _print(long long t) { cerr << t; }
void _print(int t) { cerr << t; }
void _print(string t) { cerr << t; }
void _print(char t) { cerr << t; }
void _print(long double t) { cerr << t; }
void _print(double t) { cerr << t; }
void _print(unsigned long long t) { cerr << t; }
template <class T, class V>
void _print(pair<T, V> p);
template <class T>
void _print(vector<T> v);
template <class T>
void _print(set<T> v);
template <class T>
void _print(set<T, greater<int>> v);
template <class T, class V>
void _print(map<T, V> v);
template <class T>
void _print(multiset<T> v);
template <class T, class V>
void _print(pair<T, V> p) {
  cerr << "{";
  _print(p.first);
  cerr << ",";
  _print(p.second);
  cerr << "}";
}
template <class T>
void _print(vector<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T>
void _print(set<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T>
void _print(set<T, greater<int>> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T>
void _print(multiset<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T, class V>
void _print(map<T, V> v) {
  cerr << "[ ";
  for (auto i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
bool cmp(pair<long long, long long> a, pair<long long, long long> b) {
  if (a.first - a.second > b.first - b.second) return true;
  return false;
}
void solve() {
  long long n;
  cin >> n;
  vector<pair<long long, long long>> v(n);
  for (pair<long long, long long> &it : v) cin >> it.first >> it.second;
  sort(v.begin(), v.end(), cmp);
  long long tot = 0;
  for (long long i = 0; i < n; i++) {
    tot += -v[i].first + v[i].second * n + (i + 1) * (v[i].first - v[i].second);
  }
  cout << tot << endl;
}
int32_t main() {
  file();
  long long test = 1;
  while (test--) {
    solve();
  }
}
