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{-# LANGUAGE MagicHash, UnboxedTuples #-}
import GHC.Exts
import System.Environment
main = do
[n] <- fmap (fmap read) getArgs
case g n of
(# a, b, c, d, e, f, g, h, i, j, k, l #) -> print a
-- a deep stack in which each frame is an unboxed tuple-return, to exercise
-- the stack underflow machinery.
g :: Int -> (# Int,Float,Double,
Int#,Float#,Double#,
Int,Float,Double,
Int#,Float#,Double# #)
g 0 = (# 1, 2.0, 3.0,
1#, 2.0#, 3.0##,
1, 2.0, 3.0,
1#, 2.0#, 3.0## #)
g x = case g (x-1) of
(# a, b, c, d, e, f, g, h, i, j, k, l #) ->
(# a+1, b, c, d, e, f, g, h, i, j, k, l #)
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