【checkio】Python学习--Non-unique Elements

You are given a non-empty list of integers (X). For this task, you should return a list consisting of only the non-unique elements in this list. To do so you will need to remove all unique elements (elements which are contained in a given list only once). When solving this task, do not change the order of the list. Example: [1, 2, 3, 1, 3] 1 and 3 non-unique elements and result will be [1, 3, 1, 3].

Input: A list of integers.

Output: The list of integers.

题目来自  py.checkio.org

My answer:

找到出现次数为1的元素，删除

def checkio(data):
    temp=data.copy()
    for i in temp:
        print(data.count(i))
        if data.count(i)==1:
            data.remove(i)

    return data

Other answer:

def checkio(data):

        return [i for i in data if data.count(i) > 1]