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Shootout/Binary trees

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(Proposed entry)
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Ported to ghc 6.6
 
Ported to ghc 6.6
  +
[http://alioth.debian.org/tracker/index.php?func=detail&aid=304418&group_id=30402&atid=411646 Submitted]
   
 
<haskell>
 
<haskell>

Revision as of 09:03, 2 February 2007

Contents

1 Proposals

Port the Clean entry.

2 Proposed entry

Ported to ghc 6.6 Submitted

{-# OPTIONS -fbang-patterns #-}
 
--
-- The Great Computer Language Shootout
-- http://shootout.alioth.debian.org/
--
-- Simon Marlow
-- Rewritten by Don Stewart
--
 
import System
import Data.Bits
import Text.Printf
 
data Tree = Nil | Node !Int Tree Tree
 
minDepth = 4
 
io s n t = printf "%s of depth %d\t check: %d\n" s n t
 
main = do
    maxDepth <- getArgs >>= return . max (minDepth+2) . read . head :: IO Int
 
    let stretch = make 0 (maxDepth+1)
    io "stretch tree" (maxDepth+1) (check stretch)
 
    let long    = make 0 maxDepth
 
    let vs = depth minDepth maxDepth
    mapM_ (\(P m d i) -> io (show m ++ "\t trees") d i) vs
 
    io "long lived tree" maxDepth (check long)
 
data P = P !Int !Int !Int
 
depth :: Int -> Int -> [P]
depth !d !m
    | d > m     = []
    | otherwise = P (2*n) d (sumT n d 0) : depth (d+2) m
  where
    n = 1 `shiftL` (m - d + minDepth)
 
sumT :: Int -> Int -> Int -> Int
sumT !0 !d !t = t
sumT i d t    = sumT (i-1) d (t + a + b)
    where a = check (make i    d)
          b = check (make (-i) d)
 
make :: Int -> Int -> Tree
make !i !0 = Node i Nil Nil
make  i  d = Node i (make (i2-1) d2) (make i2 d2)
    where
        i2 = 2*i
        d2 = d-1
 
check :: Tree -> Int
check Nil          = 0
check (Node i l r) = i + check l - check r

3 Old entry

Shortest entry in any language, and almost twice as fast as old entry on my box.

Was speculatively disqualified.

{-# OPTIONS_GHC -fglasgow-exts -O2 -optc-O3 -funbox-strict-fields #-}
-- The Great Computer Language Shootout
-- http://shootout.alioth.debian.org/
-- Simon Marlow
-- Shortened by Don Stewart
 
import System; import Text.Printf; import Monad
 
data Tree = Nil | Node !Int Tree Tree
 
min' = 4 :: Int
 
main = do max' <- getArgs >>= return . max (min'+2) . read . head
          printf "stretch tree of depth %d\t check: %d\n" (max'+1) (itemCheck $ make 0 (max'+1))
          depthLoop min' max'
          printf "long lived tree of depth %d\t check: %d\n" max' (itemCheck $ make 0 max')
 
depthLoop d m = when (d <= m) $ do
    printf "%d\t trees of depth %d\t check: %d\n" (2*n) d (sumLoop n d 0)
    depthLoop (d+2) m 
    where n = 2^(m - d + min')
 
sumLoop 0 d acc = acc
sumLoop k d acc = c `seq` sumLoop (k-1) d (acc + c + c')
    where (c,c')  = (itemCheck (make k d), itemCheck (make (-1*k) d))
 
make i (0::Int) = i `seq` Nil
make i  d       = Node i (make ((2*i)-1) (d-1)) (make (2*i) (d-1))
 
itemCheck Nil = 0
itemCheck (Node x l r) = x + itemCheck l - itemCheck r

4 Old Entry

{-# OPTIONS -O3 -optc-O3 #-}
-- The Great Computer Language Shootout
-- http://shootout.alioth.debian.org/
-- contributed by Einar Karttunen
 
import System
 
data Tree = Node  Int Tree Tree | Nil
 
main = do [n] <- getArgs
          let max' = max (min'+2) (read n)
          showItemCheck (max'+1) (make 0 (max'+1)) "stretch tree of depth "
          let longlived = make 0 max'
          depthLoop min' max'
          showItemCheck max' longlived "long lived tree of depth "
 
min' :: Int
min' = 4
 
showItemCheck d a s = putStrLn (s++show d++"\t check: "++show (itemCheck a))
 
showCheck i d check = putStrLn (show (2*i)++"\t trees of depth "++show d++"\t check: "++show check)
 
 
depthLoop d m | d > m = return ()
depthLoop d m         = showCheck n d (sumLoop n d 0) >> depthLoop (d+2) m
              where n = 2^(m - d + min')
 
 
 
sumLoop :: Int -> Int -> Int -> Int
sumLoop 0 d acc = acc
sumLoop k d acc = c `seq` sumLoop (k-1) d (acc + c + c')
    where c  = itemCheck (make k d)
          c' = itemCheck (make (-1*k) d)
 
make :: Int -> Int -> Tree
make i 0 = Nil
make i d = Node i (make ((2*i)-1) (d-1)) (make (2*i) (d-1))
 
itemCheck Nil = 0
itemCheck (Node x l r) = x + itemCheck l - itemCheck r