/*

78. Subsets (https://leetcode.com/problems/subsets/)

Medium

Given a set of distinct integers, nums, return all possible subsets (the power set).

Note: The solution set must not contain duplicate subsets.

Example:

Input: nums = [1,2,3]

Output:

[

[3],

[1],

[2],

[1,2,3],

[1,3],

[2,3],

[1,2],

[]

]

*/

package recusion;

import java.util.ArrayList;

import java.util.List;

public class Subsets {

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

List<List<Integer>> list = new ArrayList<>();

createItem(list, new ArrayList<Integer>(), nums, 0);

return list;

}

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

if (items != null) {

list.add(new ArrayList<Integer>(items));

}

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

items.add(nums[i]);

createItem(list, items, nums, i + 1);

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

}

}

}