【算法】【搜索和回溯】Leetcode子集

78. 子集

题目链接：https://leetcode-cn.com/problems/subsets/

class Solution {
public:
    vector<vector<int>> res;
    vector<int> path;
    vector<vector<int>> subsets(vector<int>& nums) {
        dfs(nums, 0);
        return res;
    }
    
    void dfs(vector<int>& nums, int u)
    {
        res.push_back(path);
       
        for(int i = u; i < nums.size(); i++)
        {
            path.push_back(nums[i]);
            dfs(nums, i + 1);
            path.pop_back();
        }
    }
};

90. 子集II

题目链接：https://leetcode-cn.com/problems/subsets-ii/

class Solution {
public:
    vector<vector<int>> res;
    vector<int> path;
    vector<vector<int>> subsetsWithDup(vector<int>& nums) {
        sort(nums.begin(), nums.end());
        dfs(nums, 0);
        return res;
    }
    
    void dfs(vector<int>& nums, int u)
    {
        res.push_back(path);
       
        for(int i = u; i < nums.size(); i++)
        {
            if(i > u && nums[i] == nums[i - 1]) continue;
            path.push_back(nums[i]);
            dfs(nums, i + 1);
            path.pop_back();
        }
    }
};