Created
January 3, 2015 18:13
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import Data.Char | |
largestProduct :: Int -> String -> (Int, [Int]) | |
largestProduct size n = | |
let digits = map digitToInt n in | |
findSubsequence size (0, [0]) digits | |
findSubsequence :: Int -> (Int,[Int]) -> [Int] -> (Int, [Int]) | |
findSubsequence size prev seq | |
| length seq < size = prev | |
| product <= previous = | |
findSubsequence size prev (tail seq) | |
| previous == 0 || product > previous = | |
findSubsequence size current (tail seq) | |
where subsequence = take size seq | |
product = foldl (*) 1 subsequence | |
current = (product, subsequence) | |
previous = fst prev | |
largestProduct 13 "7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450" |
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