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How can you remove every nth element of a string?
I'm guessing you would use the drop function in some kind of way.
Like this drops the first n, how can you change this so only drops the nth, and then the nth after that, and so on, rather than all?
dropthem n xs = drop n xs
401
Use list slicing to remove every Nth element from a list, e.g. del my_list[::2] . The value between the square brackets is the step which can be used to remove every Nth element from the list. Copied!
Use Array#splice method to remove an element from the array. Where the first argument is defined as the index and second as the number elements to be deleted. To remove elements at 3rd position use a while loop which iterates in backward and then delete the element based on the position.
Use the del statement with list slicing to remove every second element from a list, e.g. del my_list[::2] . The del statement will remove every second element from the list starting at the specified start index. Copied!
Simple. Take (n-1) elements, then skip 1, rinse and repeat.
dropEvery _ [] = []
dropEvery n xs = take (n-1) xs ++ dropEvery n (drop n xs)
Or in showS style for efficiency's sake
dropEvery n xs = dropEvery' n xs $ []
where dropEvery' n [] = id
dropEvery' n xs = (take (n-1) xs ++) . dropEvery n (drop n xs)
-- groups is a pretty useful function on its own!
groups :: Int -> [a] -> [[a]]
groups n = map (take n) . takeWhile (not . null) . iterate (drop n)
removeEveryNth :: Int -> [a] -> [a]
removeEveryNth n = concatMap (take (n-1)) . groups n
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