/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
        LinkedList<List<Integer>> res = new LinkedList<>();
        LinkedList<Integer> path =new LinkedList<>();
        public List<List<Integer>> pathTarget(TreeNode root, int target){
            recur(root, target);
            return res;
        }

        void recur(TreeNode root, int tar){
            if(root == null) return ;
            path.add(root.val);
            tar -= root.val;
            if(tar == 0 && root.left == null && root.right == null)
                res.add(new LinkedList(path));
            recur(root.left, tar);
            recur(root.right, tar);
            path.removeLast();
        }

}