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

int N;

signed main(){
  cin>>N;
  vector<int> A(N);
  vector<int> B(N);
  for(int i = 0; i < N; i++) cin>>A[i]>>B[i];
  vector<vector<int>> dp(N+1,vector<int>(N+1));
  for(int i = N; i > 0; i--){
  	for(int j = 0; j <= N-i; j++){
  		dp[i-1][j] = max(dp[i-1][j],dp[i][j] + A[i-1] * j);
  		dp[i-1][j+1] = max(dp[i-1][j+1],dp[i][j] + B[i-1]);
  	}
  }
  int ans = 0;
  for(int i = 0; i <= N; i++) ans = max(ans,dp[0][i]);
  cout << ans << "\n";
}