https://github.com/emahtab/count-complete-tree-nodes
Count total nodes in a Complete Binary Tree
https://github.com/emahtab/count-complete-tree-nodes
complete-binary-tree leetcode problem-solving
Last synced: about 2 months ago
JSON representation
Count total nodes in a Complete Binary Tree
- Host: GitHub
- URL: https://github.com/emahtab/count-complete-tree-nodes
- Owner: eMahtab
- Created: 2020-02-08T04:41:27.000Z (over 5 years ago)
- Default Branch: master
- Last Pushed: 2020-02-08T04:42:50.000Z (over 5 years ago)
- Last Synced: 2025-02-02T03:26:12.465Z (4 months ago)
- Topics: complete-binary-tree, leetcode, problem-solving
- Homepage:
- Size: 1000 Bytes
- Stars: 1
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# Count Complete Tree Nodes
## https://leetcode.com/problems/count-complete-tree-nodes
Given a complete binary tree, count the number of nodes.
Note:
Definition of a complete binary tree from Wikipedia:
In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the last level are as far left as possible. It can have between 1 and 2h nodes inclusive at the last level h.
```
Example:
Input:
1
/ \
2 3
/ \ /
4 5 6
Output: 6
```
# Implementation :
```java
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
class Solution {
int totalNodes = 0;
public int countNodes(TreeNode root) {
if(root == null)
return 0;
helper(root);
return totalNodes;
}
public void helper(TreeNode root){
if(root != null){
totalNodes++;
helper(root.left);
helper(root.right);
}
}
}
```