题解 | 有重复项数字的全排列

#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param num int整型一维数组 
# @return int整型二维数组
#
class Solution:
    def permuteUnique(self , num: List[int]) -> List[List[int]]:
        # write code here
        if len(num) <= 1:
            return [num]

        ret = []
        for i, e in enumerate(num):
            r = self.permuteUnique(num[:i] + num[i + 1:])
            ret += [[e] + k for k in r]
        
        result = []
        for i in ret:
            if result.count(i) == 0:
                result.append(i)

        return sorted(result)