90_subsets_II.py

class Solution:
    def subsetsWithDup(self, nums: List[int]) -> List[List[int]]:

        def backtracking(begin: int, tmp: int, length: int):
            if len(tmp) == length:
                ans.append(tmp)
            else:
                for i in range(begin, len(nums)):
                    if (i > begin) and (nums[i] == nums[i-1]):
                        continue
                    backtracking(i+1, tmp+[nums[i]], length)
        
        nums.sort()
        ans = []
        for i in range(len(nums)+1):
            backtracking(0, [], i)
        return ans

'''
    This is my personal record of solving Leetcode Problems. 
    If you have any questions, please discuss them in [Issues](https://github.com/mengxinayan/leetcode/issues).
    Copyright (C) 2020-2022  mengxinayan

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
'''