LeetCode78. Subsets

Posted 2022-12-15 zgljl2012

问题描述

Given a set of distinct integers, nums, return all possible subsets.

Note: The solution set must not contain duplicate subsets.

For example,
If nums = [1,2,3], a solution is:

[
  [3],
  [1],
  [2],
  [1,2,3],
  [1,3],
  [2,3],
  [1,2],
  []
]

算法

深度优先，回溯算法

代码

        public List<List<Integer>> subsets(int[] nums) 
            List<List<Integer>> res = new ArrayList<>();
            dfs(res, new ArrayList<>(), nums, 0);
            return res;
        

        public void dfs(List<List<Integer>> res, List<Integer> list, int[] nums, int start) 
            res.add(new ArrayList<>(list));
            for(int i=start;i<nums.length;i++) 
                list.add(nums[i]);
                dfs(res, list, nums, i+1);
                list.remove(list.size()-1);