/*
 * Program to compute length of strings various ways, as a silly 
 * example of working with strings.
 */
#include <stdio.h>

/* compute length using array and indices */
int strlen_array(char s[]) {
	int count = 0;
	while (s[count] != '\0') ++count;
	return count;
}

/* compute length using pointers */
int strlen_ptr(char *s) {
	char *p = s;
	while (*p != '\0') ++p;
	return p-s;
}

/* compute length using pointers and recursion */
int strlen_recur(char *s) {
	if (*s == '\0') return 0;
	return 1 + strlen_recur(s+1);
}

/* try various functions, printing input and outputs */
void tryfcns(char *s) {
	printf("'%s' %d %d %d\n", s, 
			strlen_array(s), strlen_ptr(s), strlen_recur(s));
}

int main(void) {
	tryfcns("hello");
	tryfcns("a somewhat longer string");
	return 0;
}