using System;

public class Program

{

    public static void Main()

    {

        int x = int.Parse(Console.ReadLine());

        int a, b = 0;

        a=x;

        while (a != 0)

        {

            b = b*10 + a%10;

            a = a / 10;

        }

        if (x < 100) Console.WriteLine(x*b);

        else if ( x > 1000) Console.WriteLine(x+b);

            Console.WriteLine(a-b);

    }

}