# Difference between revisions of "99 questions/Solutions/82"

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(Solution to Problem 82 using list comprehension added) |
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arrive = fst split | arrive = fst split | ||

go ls = [ x ++ [snd y] | x <- ls, y <- g, last x == fst y, not (snd y `elem` tail x)] | go ls = [ x ++ [snd y] | x <- ls, y <- g, last x == fst y, not (snd y `elem` tail x)] | ||

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+ | [[Category:Programming exercise spoilers]] |

## Revision as of 03:49, 10 January 2017

Brute-force search from the source, using list comprehension:

import Data.List (partition) cycle' :: Int -> [(Int, Int)] -> [ [Int] ] cycle' n g = search n [] where search [] result = result search cur result = search (go active) (arrive ++ result) where split = partition end cur end s = (last s == n) && (length s /= 1) active = snd split arrive = fst split go ls = [ x ++ [snd y] | x <- ls, y <- g, last x == fst y, not (snd y `elem` tail x)]