compare speed of loop with Python and C.

tarai.c

#include <stdio.h>

int counter = 0;

int tarai(int x, int y, int z) {
	counter++;
	if (x <= y) return y;
	else return tarai(tarai(x-1, y, z), tarai(y-1, z, x), tarai(z-1, x, y));
}

int main(int argc, char* argv[]) {
	int result = tarai(12, 6, 0);
	printf("tarai(12, 6, 0) = %d\t<n_call:%d>\n", result, counter);
	return 0;
}

tarai.py

#!/usr/bin/python

counter = 0

def tarai(x, y, z):
    global counter
    counter += 1

    if x <= y:
        return y
    else:
        return tarai(tarai(x-1,y,z), tarai(y-1,z,x), tarai(z-1,x,y))

if __name__ == '__main__':
    print("tarai(12, 6, 0) = {}\t<n_call:{}>".format(tarai(12, 6, 0), counter))