红题居然MLE了

count' :: Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> Int -> String -> [Int] count' zero one two three four five six seven eight nine [] = [zero, one, two, three, four, five, six, seven, eight, nine] count' zero one two three four five six seven eight nine ('0':str) = count' (zero + 1) one two three four five six seven eight nine str count' zero one two three four five six seven eight nine ('1':str) = count' zero (one + 1) two three four five six seven eight nine str count' zero one two three four five six seven eight nine ('2':str) = count' zero one (two + 1) three four five six seven eight nine str count' zero one two three four five six seven eight nine ('3':str) = count' zero one two (three + 1) four five six seven eight nine str count' zero one two three four five six seven eight nine ('4':str) = count' zero one two three (four + 1) five six seven eight nine str count' zero one two three four five six seven eight nine ('5':str) = count' zero one two three four (five + 1) six seven eight nine str count' zero one two three four five six seven eight nine ('6':str) = count' zero one two three four five (six + 1) seven eight nine str count' zero one two three four five six seven eight nine ('7':str) = count' zero one two three four five six (seven + 1) eight nine str count' zero one two three four five six seven eight nine ('8':str) = count' zero one two three four five six seven (eight + 1) nine str count' zero one two three four five six seven eight nine ('9':str) = count' zero one two three four five six seven eight (nine + 1) str

count :: Int -> Int -> [Int] count begin end = count' 0 0 0 0 0 0 0 0 0 0 $ foldr (\x l -> show x ++ l) [] [begin..end]

main :: IO () main = do [begin, end] <- (map read . words) <$> getLine

putStrLn $foldr (\x l -> show x ++ " " ++ l) []$ count begin end

return ()

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