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/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    vector<vector<int>> res;
    vector<vector<int>> pathSum(TreeNode* root, int targetSum) {
        vector<int> path;
        int currSum=0;
        dfs(root, path, currSum, targetSum);
        return res;
    }

    void dfs(TreeNode* root, vector<int> &path, int currSum, int targetSum){
        if(!root) return;
        path.push_back(root->val);
        currSum += root->val;
        if(!(root->left) && !(root->right) && currSum == targetSum){
            res.push_back(path);
        }
        else{
            dfs(root->left, path, currSum, targetSum);
            dfs(root->right, path, currSum, targetSum);
        }
        currSum -= root->val;
        path.pop_back();
    }

};