# [90. 子集 II](https://leetcode-cn.com/problems/subsets-ii) [English Version](/solution/0000-0099/0090.Subsets%20II/README_EN.md) ## 题目描述 <!-- 这里写题目描述 --> <p>给你一个整数数组 <code>nums</code> ,其中可能包含重复元素,请你返回该数组所有可能的子集(幂集)。</p> <p>解集 <strong>不能</strong> 包含重复的子集。返回的解集中,子集可以按 <strong>任意顺序</strong> 排列。</p> <div class="original__bRMd"> <div> <p> </p> <p><strong>示例 1:</strong></p> <pre> <strong>输入:</strong>nums = [1,2,2] <strong>输出:</strong>[[],[1],[1,2],[1,2,2],[2],[2,2]] </pre> <p><strong>示例 2:</strong></p> <pre> <strong>输入:</strong>nums = [0] <strong>输出:</strong>[[],[0]] </pre> <p> </p> <p><strong>提示:</strong></p> <ul> <li><code>1 <= nums.length <= 10</code></li> <li><code>-10 <= nums[i] <= 10</code></li> </ul> </div> </div> ## 解法 <!-- 这里可写通用的实现逻辑 --> <!-- tabs:start --> ### **Python3** <!-- 这里可写当前语言的特殊实现逻辑 --> ```python class Solution: def subsetsWithDup(self, nums: List[int]) -> List[List[int]]: def dfs(nums, i, res, path): res.append(copy.deepcopy(path)) for j in range(i, len(nums)): if j != i and nums[j] == nums[j - 1]: continue path.append(nums[j]) dfs(nums, j + 1, res, path) path.pop() res, path = [], [] nums.sort() dfs(nums, 0, res, path) return res ``` ### **Java** <!-- 这里可写当前语言的特殊实现逻辑 --> ```java class Solution { public List<List<Integer>> subsetsWithDup(int[] nums) { List<Integer> path = new ArrayList<>(); List<List<Integer>> res = new ArrayList<>(); Arrays.sort(nums); dfs(nums, 0, res, path); return res; } private void dfs(int[] nums, int i, List<List<Integer>> res, List<Integer> path) { res.add(new ArrayList<>(path)); for (int j = i; j < nums.length; ++j) { if (j != i && nums[j] == nums[j - 1]) { continue; } path.add(nums[j]); dfs(nums, i + 1, res, path); path.remove(path.size() - 1); } } } ``` ### **...** ``` ``` <!-- tabs:end -->