#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;

int main() {
    int boards_count;
    cin >> boards_count;
    vector<uint64_t> boards_lengths(boards_count);
    for (uint64_t& length : boards_lengths) {
        cin >> length;
    }

    sort(begin(boards_lengths), end(boards_lengths));
    uint64_t result = 0;
    for (uint64_t i = 0; i < boards_lengths.size(); ++i) {
        result = max(result, boards_lengths[i] * (boards_lengths.size() - i));
    }

    cout << result;
}
/*
test1
5
1 2 3 4 5

9
*/