10 lines
151 B
Haskell
10 lines
151 B
Haskell
{-# LANGUAGE PostfixOperators #-}
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(!) :: Integer -> Integer
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(!) 0 = 1
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(!) n = n * (pred n !)
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main :: IO ()
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main = do
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print (5 !)
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print ((4 !) !)
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