def is_prime(n)
  if n < 2 then return false end  
  for i in 2..n
    if n % i == 0 then return false end
  end
  return true
end

def print_all_primes(n)
  for i in 0..n
    if is_prime(i) then print(i) end
  end
end


print_all_primes(10)