package com.q0078_subsets;

import java.util.ArrayList;

import java.util.List;

/**

* @author xjn

* @since 2020-02-01

* https://leetcode-cn.com/problems/subsets/

* 78. 子集

*/

public class Solution {

private List<List<Integer>> resList = new ArrayList<>();

public List<List<Integer>> subsets(int[] nums) {

if (nums == null || nums.length == 0) {

return resList;

}

subsets(nums, 0, new ArrayList<>());

return resList;

}

private void subsets(int[] nums, int start, List<Integer> list) {

resList.add(new ArrayList<>(list));

for (int i = start; i < nums.length; i++) {

list.add(nums[i]);

subsets(nums, i + 1, list);

list.remove(list.size() - 1);

}

}

public static void main(String[] args) {

Solution test = new Solution();

System.out.println(test.subsets(new int[]{1, 2, 3}));

}

}