[checkIO]Home 05.Non-unique Elements

If you have 50 different plug types, appliances wouldn't be available and would be very expensive. But once an electric outlet becomes standardized, many companies can design appliances, and competition ensues, creating variety and better prices for consumers.

-- Bill Gates

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].

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Input: A list of integers.

Output: An iterable of integers.

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Example:

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

checkio([1, 2, 3, 4, 5]) == []

checkio([5, 5, 5, 5, 5]) == [5, 5, 5, 5, 5]

checkio([10, 9, 10, 10, 9, 8]) == [10, 9, 10, 10, 9]

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* 유니크한 숫자 제거하기

 

 

- 풀이

 

def checkio(data: list) -> list:
    newlist = []
    for i in data:
        if data.count(i) > 1:
            newlist.append(i)
    
    return newlist