strlen with no conditionals

strlen.c

#include <stdio.h>

typedef int (*strlen_f)(char *);
int plus_one(char *);
int ret_zero(char *);
int _strlen(char *);

strlen_f funcs[2] = {ret_zero, plus_one};

int plus_one(char * c) {
	return 1 + _strlen(c+1);
}

int ret_zero(char * c) {
	return 0;
}

int _strlen(char * s) {
	return funcs[!!(*(s))](s);
}


int main(int argc, char * argv[]) {
	printf("%s:%d\n", argv[1], _strlen(argv[1]));
}