LeetCode:Subsets

问题描述：

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

Note:

• Elements in a subset must be in non-descending order.
• The solution set must not contain duplicate subsets.

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

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

代码：

vector<vector<int> > Solution::subsets(vector<int> &S){    sort(S.begin(),S.end());    int vector_length = S.size();    int subsets_num = 1 << vector_length;    vector<vector<int> > result;    for(int i = 0;i < subsets_num;i++)    {        vector<int> subset;        for(int j = 0;j < vector_length;j++)        {            if(i & (1 << j))                subset.push_back(S[j]);        }        result.push_back(subset);    }    return result;}