tarai.c

#include "stdio.h"
#include "time.h"

int main(int argc, char const *argv[])
{
  clock_t t1, t2;
	t1 = clock();
	tarai(13,5,0);
	t2 = clock();
	printf("finished in %d ms\n",(int)(t2-t1));
	return 0;

}

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

tarai.rb

t1 = Time.now

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

tarai(13,5,0)

puts (Time.now - t1) + 'sec'

tarai.scm

(define (tarai x y z)
  (if (<= x y)
  	y
		(tarai 
			(tarai (- x 1) y z)
			(tarai (- y 1) z x)
			(tarai (- z 1) x y))))

(print (time (tarai 13 5 0)))