#include <iostream>
#include <vector>
using namespace std;

using ll = long long;

const ll INF = 1ll << 60;

int main() {
  int N;
  cin >> N;
  vector<ll> A(N), B(N);
  for (int i = 0; i < N; i++) cin >> A[i] >> B[i];
  vector<ll> dp(N + 1, -INF);
  dp[0] = 0;
  for (int i = N - 1; i >= 0; i--) {
    vector<ll> ndp(N + 1, -INF);
    for (int j = 0; j <= N; j++) {
      if (dp[j] == -INF) continue;
      // A
      ndp[j] = max(ndp[j], dp[j] + A[i] * j);
      // B
      ndp[j + 1] = max(ndp[j + 1], dp[j] + B[i]);
    }
    dp = ndp;
  }
  ll res = -INF;
  for (int j = 0; j <= N; j++) res = max(res, dp[j]);
  cout << res << endl;
  return 0;
}