C++ 排列组合Leetcode

#include
#include

using namespace std;

class Solution {
public:
    vector> permute(vector nums) {

        vector> res;
        if(nums.size()==0) {
            return res;
        }
        helper(nums, 0, res);
        return res;
    }

    void helper(vector nums, int start, vector>& res) {
        if(start==nums.size()-1) {
            res.push_back(nums);
            return; 
        }

        for(int i=start;i nums {1,2,3};
    vector> res;
    Solution s2;
    res = s2.permute(nums);
    for(auto i:res) {
        for(auto j:i){
            cout< 
 
子集 

#include
#include

using namespace std;

class Solution {
public:
    vector> res;
    vector> subsets(vector& nums) {
        vector track;
        backtrace(nums,0,track);
        return res;
    }   

    void backtrace(vector &nums, int start, vector & track) {
        res.push_back(track);
        for(int i= start;i nums {1,2,3};
    Solution s2;
    vector> res;
    res = s2.subsets(nums);
    for(auto i:res) {
        for(auto j:i) {
            cout<