#include <iostream>
#include <vector>


int main() {
    int numbers_amount;
    std::cin >> numbers_amount;
    std::vector<int> histogram(numbers_amount + 2, -1);
    for (int index = 1; index <= numbers_amount; ++index) {
        std::cin >> histogram[index];
    }
    std::vector<int> right(numbers_amount + 2);
    std::vector<int> stack(1, 0);
    for (int index = 1; index <= numbers_amount + 1; ++index) {
        while (histogram[index] < histogram[stack.back()]) {
            right[stack.back()] = index;
            stack.pop_back();
        }
        stack.push_back(index);
    }
    int64_t max_square = 0;
    std::vector<int> left(numbers_amount + 2, 0);
    for (int index = numbers_amount; index >= 0; --index) {
        while (histogram[index] < histogram[stack.back()]) {
            int a = stack.back();
            stack.pop_back();
            left[a] = index;
            int64_t current_square = static_cast<int64_t>(histogram[a]) * (right[a] - left[a] - 1);
            if (current_square > max_square) {
                max_square = current_square;
            }
        }
        stack.push_back(index);
    }
    std::cout << max_square;
    return 0;
}