题目链接

90. 子集 II

思路

去重方法与【DFS】LeetCode 40. 组合总和 II思路相似

代码

class Solution {
    private List<List<Integer>> result = new ArrayList<>();
    private Deque<Integer> path = new ArrayDeque<>();

    public List<List<Integer>> subsetsWithDup(int[] nums) {
        Arrays.sort(nums);

        dfs(0, nums);

        return result;
    }

    void dfs(int index, int[] nums){
        result.add(new ArrayList<>(path));

        if(index >= nums.length){
            return;
        }

        for(int i = index; i < nums.length; i++){
            if(i != index && nums[i - 1] == nums[i]){
                continue;
            }
            path.addLast(nums[i]);
            dfs(i + 1, nums);
            path.removeLast();
        }
    }
}