array.diff 练习源码

Your goal in this kata is to implement a difference function, which subtracts one list from another and returns the result.

It should remove all values from list a, which are present in list b.

array_diff([1,2],[1]) == [2]
If a value is present in b, all of its occurrences must be removed from the other:

array_diff([1,2,2,2,3],[2]) == [1,3]

方法一

def array_diff(a, b):
    for i in b:
        while i in a:
            a.remove(i)
    return a

方法二

def array_diff(a, b):
    return [i for i in a if i not in b]