129. Sum Root to Leaf Numbers
https://leetcode.com/problems/sum-root-to-leaf-numbers/
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.
Note: A leaf is a node with no children.
Example:
Input: [1,2,3] 1 / \ 2 3 Output: 25 Explanation: The root-to-leaf path1->2
represents the number12
. The root-to-leaf path1->3
represents the number13
. Therefore, sum = 12 + 13 =25
.
Example 2:
Input: [4,9,0,5,1] 4 / \ 9 0 / \ 5 1 Output: 1026 Explanation: The root-to-leaf path4->9->5
represents the number 495. The root-to-leaf path4->9->1
represents the number 491. The root-to-leaf path4->0
represents the number 40. Therefore, sum = 495 + 491 + 40 =1026
.