module Euler7

imports
  Prelude
  Data.Stack

where

main :: () -> I32
main () = do
  p = new (stack #10001)
  primes p
  case new (pop p) of
    Nothing -> assert False
    Just i -> do
      assert (@i == 104743)
      putW @i
  0

primes :: Ptr (Stack #cnt W32) -> ()
primes p => do
  empty p
  b = new (push 2 p)
  for 3 (\_ -> not (is_full p)) (add 2)
    (\i -> when (not (any (is_factor i) p)) (b <- push i p))

is_factor :: { Arith a, Eq a } => a -> a -> Bool
is_factor x y => (x % y) == 0