Haskell Wins! 1-liner
This is why Haskell is so beautiful:\n\nsolve :: String -> String\nsolve = concat \n      . map (tail . init) \n      . groupBy (\\a b -> [a,b] /= ")(")\n\nThe 
This is why Haskell is so beautiful:\n```\nsolve :: String -> String\nsolve = concat \n      . map (tail . init) \n      . groupBy (\\a b -> [a,b] /= ")(")\n```\nThe one-liner would be:\n```\nsolve = concat . map (tail . init) . groupBy (\\a b -> [a,b] /= ")(")\n```
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