# coding: utf-8


class Solution:

    def duplicate(self,alist):
        """返回陣列中重複的數字"""
        tmp = []
        for item in alist:
            if alist.count(item) > 1:
                tmp.append(item)
        tmp = list(set(tmp))
        return tmp

if __name__ == '__main__':
    a_list = [1, 3, 5, 3, 1, 2, 1, 6]
    obj = Solution()
    dup = obj.duplicate(a_list)
    print(dup)