【LeetCode】C# 78、Subsets

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],
[]
]

给定一个集合，返回其所有子集合，包括空集。

思路：迭代，和上一题类似，不同的是这题把所有情况都录入result。

public class Solution {    public List<List<int>> Subsets(int[] nums) {        List<List<int>> list = new List<List<int>>();        Array.Sort(nums);        backtrack(list, new List<int>(), nums, 0);        return list;    }    private void backtrack(List<List<int>> list , List<int> tempList, int [] nums, int start){        list.Add(new List<int>(tempList));        for(int i = start; i < nums.Length; i++){            tempList.Add(nums[i]);            backtrack(list, tempList, nums, i + 1);            tempList.RemoveAt(tempList.Count - 1);        }    }}