/* 
 * Program to demonstrate/test user-written string-length function.
 * (Note that there is a library function strlen that does the same thing,
 * so this is purely for pedagogical purposes!)
 */
#include <stdio.h>

/* count and return number of characters in input */
/* (uses pointer to access individual characters) */
int string_length(char * input) {
	int count = 0;
	for (char* p = input; *p != '\0' ; ++p) {
        ++count;
	}
	return count;
}
/* test/demonstrate string_length function */
void test_string_length(char * input) {
    printf("length of '%s' is %d\n", input, string_length(input));
}

/* main */
int main(void) {
    test_string_length("hello");
    test_string_length("hello world");
	return 0;	
}