列表内相邻项的差值

有这样一道题，有一组数字 245 84 180 230 360 ，问那两个数字相差最小？

比较常见的算法是排序然后求相邻两个数字之间的差。

plusList :: Num a => [a] -> [a]
plusList [] = []
plusList (x:[]) = [x]
plusList (x:y:[]) = [y-x]
plusList (x:y:xs) = (y-x):(plusList $ y:xs)

*Main Data.List> sort  [245,84,180,230,360]
[84,180,230,245,360]
*Main Data.List> plusList $ sort  [245,84,180,230,360]
[96,50,15,115]
测试一下