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Haskell Quiz/Maximum Sub-Array/Solution Jkramar

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< Haskell Quiz | Maximum Sub-Array(Difference between revisions)
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Line 3: Line 3:
 
<haskell>
 
<haskell>
 
maxSubArray xs = drop from$take to xs where
 
maxSubArray xs = drop from$take to xs where
sums = zip (scanl (+) 0 xs) [0..]
+
sumswithpos = zip (scanl (+) 0 xs) [0..]
 
diff ((a,ai),(b,bi)) = (a-b,(bi,ai))
 
diff ((a,ai),(b,bi)) = (a-b,(bi,ai))
(from,to) = snd$maximum$map diff$zip sums$scanl1 min sums
+
(from,to) = snd$maximum$map diff$zip sumswithpos$scanl1 min sumswithpos
 
</haskell>
 
</haskell>

Revision as of 20:01, 19 November 2008


maxSubArray xs = drop from$take to xs where
  sumswithpos = zip (scanl (+) 0 xs) [0..]
  diff ((a,ai),(b,bi)) = (a-b,(bi,ai))
  (from,to) = snd$maximum$map diff$zip sumswithpos$scanl1 min sumswithpos