"Leetcode-Interview algorithm classic-java implementation" "129-sum root to Leaf Numbers (all the numbers that are composed of root to leaf node groups)"

"129-sum root to Leaf Numbers (all the numbers that are composed of root to leaf node groups)" "leetcode-Interview algorithm classic-java Implementation" "All topics Directory Index" Original Question

Given a binary tree containing digits from 0-9 to, 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 to the sum = 12 + 13 = 25 .

Main Topic

Given a binary tree, the value of each node is 0-9, the root-to-leaf form a number, and the number of all roots to the leaf is calculated.

Thinking of solving problems

The backtracking method is used.

Code Implementation

Algorithm implementation class

 Public classSolution {Private intresult =0;//Record the total results    Private intnum =0;//record root to leaf number     Public int sumnumbers(TreeNode Root) {sum (root);returnResult }Private void sum(TreeNode Root) {if(Root! =NULL) {num = num*Ten+ Root.val;//has reached the root node.            if(Root.left = =NULL&& Root.right = =NULL{result + = num;            } sum (Root.left);            SUM (root.right); Num/=Ten; }    }}

Evaluation Results

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"Leetcode-Interview algorithm classic-java implementation" "129-sum root to Leaf Numbers (all the numbers that are composed of root to leaf node groups)"