changeFloor :: Int -> Char -> Int
changeFloor currentFloor instruction
    | instruction == increment = currentFloor + 1
    | instruction == decrement = currentFloor - 1
    | otherwise = currentFloor
changeFloor :: Int -> Char -> Int
changeFloor currentFloor instruction
    | instruction == increment = currentFloor + 1
    | instruction == decrement = currentFloor - 1
    | otherwise = currentFloor
changeFloor currentFloor instruction
    | instruction == increment = currentFloor + 1
    | instruction == decrement = currentFloor - 1
    | otherwise = currentFloor