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

void executeTime() {
    cerr << "Time Taken: " << (float)clock() / CLOCKS_PER_SEC << " secs";
}

#define int long long

int32_t main() {

    int n; cin >> n;

    vector<array<int, 2>> v(n);
    for (auto &x : v) {
        cin >> x[0] >> x[1];
    }

    sort(v.begin(), v.end(), [&](auto & x, auto & y) {
        return (x[0] - x[1]) > (y[0] - y[1]);
    });

    int ans = 0;

    for (int32_t i = 0; i < n; i++) {
        ans += (v[i][0] - v[i][1]) * (i + 1) + v[i][1] * n - v[i][0];
    }

    cout << ans;



    executeTime();
    return 0;
}