#include <stdio.h>
#include <stdlib.h>

static unsigned int hash(char *str)
{
	unsigned int hash = 0;
	char *p;

	for (p = str; *p != '\0'; p++)
		hash += (int) *p;

	return hash;
}

static void hello(char *name)
{
	if (name != NULL)
		printf("Hello, %s! You are %u\n", name, hash(name));
}

int main(int argc, char **argv)
{
	int i;

	if (argc == 1)
		hello(getenv("USER"));

	for (i = 1; i < argc; i++)
		hello(argv[i]);

	exit(EXIT_SUCCESS);
}