using System;
using System.Linq;

class No722
{
    static void Main()
    {
        var num = Console.ReadLine().Split(' ').Select(x => Int64.Parse(x)).ToArray();
        var isAnzan = (num[0] % 100) == 0 && (num[1] % 100) == 0;
        var a = num[0] * num[1];
        var ans = isAnzan ? a / 10 : -99999998 < a || a < 10000000 ? a : 'E';
        Console.WriteLine(ans);
    }
}