/*
 * Silly program to illustrate working with strings in different ways,
 * in particular finding their length.
 * (For illustration purposes only, since in practice one would almost
 * surely just use library function strlen().)
 */
#include <stdio.h>

int length_a(char s[]) {
    int count = 0;
    while (s[count] != '\0') ++count;
    return count;
}

int length_p(char *s) {
    char * p = s;
    while (*p != '\0') ++p;
    return p-s;
}

int length_r(char *s) {
    if (*s == '\0')
        return 0;
    else
        return 1 + length_r(s+1);
}

void test_it(char *s) {
    printf("for string '%s', lengths are %d, %d, %d\n",
            s, length_a(s), length_p(s), length_r(s));
}

int main(void) {
    test_it("hello world");
    test_it("");
    test_it("a");
    return 0;
}