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99 Elm Problems/Problem 10
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Run-length encode a list of tuples. Output runs of equal elements as tuples (n, e) where n is the number of duplicates of the element e.
import Html exposing (text)
import List
runLengthEncode : List a -> List (a, Int)
-- your implementation goes here
main = text <| toString <|
runLengthEncode [1, 1, 1, 2, 3, 3, 3, 4, 4, 4, 4, 5, 6, 6]
Result:
[ ( 1, 3 ), ( 2, 1 ), ( 3, 3 ), ( 4, 4 ), ( 5, 1 ), ( 6, 2 ) ]
Solutions