chap2.3

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

int main(int argc, string argv[])

{
    if (argc != 2)
    { 
        printf("You need to provide the name in the command line.\n");
        return 1;
    }
    else
    {
        printf("hello, %s\n", argv[1]);
        return 0;
    }
}