2_B_v2

#include <cmath>
#include <iostream>
#include <stack>
#include <vector>

using std::cin;
using std::cout;
using std::max;
using std::min;
using std::stack;
using std::string;
using std::vector;
using Ll = long long;
using Pll = std::pair<long long, long long>;

int main() {
  int num;
  cin >> num;
  vector<Ll> arr(num);
  for (Ll& el : arr) {
    cin >> el;
  }
  vector<int> rt(num);
  vector<int> lt(num);
  rt[num - 1] = num;
  lt[0] = -1;
  stack<Pll> st;
  st.push({arr[num - 1], num - 1});
  for (int i = num - 2; i >= 0; --i) {
    while (!st.empty() && arr[i] <= st.top().first) {
      st.pop();
    }
    if (st.empty()) {
      rt[i] = num;
    } else {
      rt[i] = st.top().second;
    }
    st.push({arr[i], i});
  }

  while (!st.empty()) {
    st.pop();
  }
  st.push({arr[0], 0});
  for (int i = 1; i < num; ++i) {
    while (!st.empty() && arr[i] <= st.top().first) {
      st.pop();
    }
    if (!st.empty()) {
      lt[i] = st.top().second;
    } else {
      lt[i] = -1;
    }
    st.push({arr[i], i});
  }
  Ll ans = -1;
  for (int i = 0; i < num; ++i) {
    Ll now = (rt[i] - lt[i] - 1) * arr[i];
    ans = max(ans, now);
  }
  cout << ans;
}