#include <cs50.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>


int main(int argc, string argv[1])
{
    if (argc == 2)
    {

        for (int  j = 0, n = strlen(argv[1]); j < n ; j++)
        {


            if (isdigit(argv[1][j]))
            {

                printf("%c", (argv[1][j]));

            }

        }
        printf ("\n");
        printf("Success\n");
    }


    else
    {
        printf("Usage: ./caesar key\n");

        return 1;

    }



}