隣り合う二項の差

Haskell 30分プログラム

30分プログラム、その145。隣り合う二項の差。

ちょっと指が痛いので、簡単に。

使い方

*Main> diff [3,1,4,1,5,9,2,6,5]
[-2,3,-3,4,4,-7,4,-1]

ソースコード

diff :: Num a=>[a]->[a]
diff [] = []
diff [_] = []
diff (x:xs@(y:_)) = (y-x):diff xs

参考