559. Maximum Depth of N-ary Tree

Easy

19218

1.題目描述

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.

For example, given a 3-ary tree:

We should return its max depth, which is 3.

Note:

1. The depth of the tree is at most 1000.
2. The total number of nodes is at most 5000

2.題目思路

簡單遞迴，最深的深度 = 目前所在結點孩子結點最深的深度 + 1（該結點到孩子結點的深度）

3.實現程式碼

/*
// Definition for a Node.
class Node {
public:
    int val;
    vector<Node*> children;

    Node() {}

    Node(int _val, vector<Node*> _children) {
        val = _val;
        children = _children;
    }
};
*/
class Solution {
public:
    int maxDepth(Node* root) {
        if (root==NULL)
            return 0;
        else {
            int dep = 0;
            for (auto it: root->children)//用來遍歷children容器
                dep = max(maxDepth(it),dep);
            dep ++;
            return dep;
        }
    }
};