import java.util.*; /* * public class TreeNode { * int val = 0; * TreeNode left = null; * TreeNode right = null; * } */ public class Solution { public int sum = 0; /** * * @param root TreeNode类 * @return int整型 */ public int sumNumbers (TreeNode root) { if (root == null) { return 0; } treeDeep(root); return sum; } public void treeDeep (TreeNode root) { if (root == null) { return; } if (root.left == null && root.right == null) { sum += root.val; return; } if (root.left != null) { root.left.val += root.val * 10; } if (root.right != null) { root.right.val += root.val * 10; } sumNumbers(root.left); sumNumbers(root.right); } }