问题描述:
Given a binary tree containing digits from 0-9
only, each root-to-leaf path could represent a number.
An example is the root-to-leaf path 1->2->3
which represents the number
123
.
Find the total sum of all root-to-leaf numbers.
For example,
1 / 2 3
The root-to-leaf path 1->2
represents the number 12
.
The root-to-leaf path 1->3
represents the number 13
.
Return the sum = 12 + 13 = 25
.
代码:
public int sumNumbers(TreeNode root) { //Java if (root == null) return 0; return sumR(root, 0); } public int sumR(TreeNode root, int x) { if (root.right == null && root.left == null) return 10 * x + root.val; int val = 0; if (root.left != null) val += sumR(root.left, 10 * x + root.val); if (root.right != null) val += sumR(root.right, 10 * x + root.val); return val; }
[leetcode]Sum Root to Leaf Numbers
原文地址:http://blog.csdn.net/chenlei0630/article/details/42276257