LeetCode-in-All
104. Maximum Depth of Binary Tree
Easy
Given the root of a binary tree, return its maximum depth.
A binary tree’s maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
Example 1:
Input: root = [3,9,20,null,null,15,7]
Output: 3
Example 2:
Input: root = [1,null,2]
Output: 2
Constraints:
- The number of nodes in the tree is in the range
[0, 104]. -100 <= Node.val <= 100
Solution
type TreeNode struct {
Val int
Left *TreeNode
Right *TreeNode
}
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
func maxDepth(root *TreeNode) int {
return traverseAndCount(root, 0)
}
func traverseAndCount(root *TreeNode, counter int) int {
if root == nil {
return counter
}
counter++
cl := traverseAndCount(root.Left, counter)
cr := traverseAndCount(root.Right, counter)
if cl > cr {
return cl
} else {
return cr
}
}