(*# P31 (**) Determine whether a given integer number is prime.
# 
# Example:
# * (is-prime 7)
# T *)

let is_prime n =
	let rec iterate i =
		if ( i * i > n  )
		then true
		else
			if ( ( n mod i ) = 0 )
			then false
			else iterate ( n + 1 )
	in
		iterate 2;;

if ( is_prime 37 ) 
then ( Printf.printf "ok\n" )
else ( Printf.printf "failed\n" );;