 Solution

ID: past-exam-of-the-year-1-of-the-computer-science-course-of-the-university-of-oxford/2018/functional-programming-design-and-analysis-of-algorithms/2/e/solution

plus, minus :: Num a => [a] -> [a] -> [a]
plus  = zipWith (+)
minus = zipWith (-)

Here every valid input is an infinite coefficient list. If finite polynomial coefficient lists were admitted, they would need zero-padding before these definitions: ordinary list zip otherwise truncates to the shorter length.

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