題目描述:
代碼實現:
- 遞歸法,分別檢索左右節點,逐步遞歸即可。
- 時間複雜度:O(n)
/**
* Definition for a binary tree node.
* function TreeNode(val) {
* this.val = val;
* this.left = this.right = null;
* }
*/
/**
* @param {TreeNode} root
* @return {number}
*/
var maxDepth = function(root) {
if (!root) {
return 0
} else {
var left = maxDepth(root.left)
var right = maxDepth(root.right)
return Math.max(left, right) + 1
}
};