Untitled

#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

int get_value(string str) {
  if (any_of(str.begin(), str.end(), ::isdigit)) {
    int value = 0;
    for (char c : str) {
      if (isdigit(c)) {
        value *= 10;
        value += c - '0';
      }
    }
    return value;
  } else {
    return str.length();
  }
}

int find_max_product(vector<string> arr) {
  int max_product = 0;
  for (int i = 0; i < arr.size(); i++) {
    for (int j = i + 1; j < arr.size(); j++) {
      int product = get_value(arr[i]) * get_value(arr[j]);
      max_product = max(max_product, product);
    }
  }
  return max_product;
}

int main() {
  int n;
  cin >> n;
  vector<string> arr(n);
  for (int i = 0; i < n; i++) {
    cin >> arr[i];
  }

  int max_product = find_max_product(arr);
  cout << max_product << endl;

  return 0;
}