题解 | #二叉树中和为某一值的路径(二)#

/**
public class TreeNode {
    int val = 0;
    TreeNode left = null;
    TreeNode right = null;

    public TreeNode(int val) {
        this.val = val;

    }

}
*/
public class Solution {
    LinkedList<Integer> list = new LinkedList<>();
    ArrayList<ArrayList<Integer>> paths = new ArrayList<>();
    public ArrayList<ArrayList<Integer>> FindPath(TreeNode root,int expectNumber) {
       if(root == null){
           return paths;
       }
        list.add(root.val);
        expectNumber = expectNumber - root.val;
        if(expectNumber == 0 && root.left == null && root.right == null){
            paths.add(new ArrayList<>(list));
        }
        FindPath(root.left,expectNumber);
        FindPath(root.right,expectNumber);
        list.removeLast();
        return paths;
    }
   
}