leetcode

0 class Solution {

1 vector<vector<int>> res;

2 vector<int> seq;

3

4 public:

5 vector<vector<int>> findSubsequences(vector<int> &nums) {

6 dfs(nums, 0);

7 return res;

8 }

9

10 void dfs(vector<int> &nums, int pos) {

11 if (seq.size() > 1) res.push_back(seq);

12 unordered_set<int> hash;

13 for (int i = pos; i < nums.size(); i++) {

14 if ((seq.empty() || nums[i] >= seq.back()) && !hash.count(nums[i])) {

15 seq.push_back(nums[i]);

16 dfs(nums, i + 1);

17 seq.pop_back();

18 hash.insert(nums[i]);

19 }

20 }

21 }

22 };