---
# System prepended metadata

title: Leetcode 559. Maximum Depth of N-ary Tree
tags: [BFS, Leetcode]

---

# Leetcode 559. Maximum Depth of N-ary Tree
###### tags: `Leetcode` `BFS`

題目 
Given a n-ary tree, find its maximum depth.

The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.

Nary-Tree input serialization is represented in their level order traversal, each group of children is separated by the null value (See examples).


Example 1:

Example 1:



Input: root = [1,null,3,2,4,null,5,6]
Output: 3
Example 2:



Input: root = [1,null,2,3,4,5,null,null,6,7,null,8,null,9,10,null,null,11,null,12,null,13,null,null,14]
Output: 5

解法:
1.這題可以從二元樹找最深的那題延伸
2.因為是要找最深的，判斷方式就是找當下的root的所有節點他們有最深的那個節點(看for-loop內)

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝

```
/**
 * Definition for a Node.
 * struct Node {
 *     int val;
 *     int numChildren;
 *     struct Node** children;
 * };
 */

int maxDepth(struct Node* root) {
    if(root == NULL)
        return 0;
    int res = 0;
    for(int i = 0; i<root->numChildren; i++)
        res = fmax(res, maxDepth(root->children[i]));
    return res+1;
}
```