“equal to” versus “not equal to” operators in an if-else statement [closed]

Answer 1

It's just a coding style issue. I hate nesting the main logic, I'll write it as:

int main(int argc, string argv[])
{
    if (argc != 2) 
    {
        printf("ERROR: Please only enter a single key! \n");
        return 1;
    }

    string msg = GetString();
}

BTW: The signatrue of main should be int main(int argc, char *argv[]).