1 //递归方法
2 /**
3 * Definition for a binary tree node.
4 * struct TreeNode {
5 * int val;
6 * TreeNode *left;
7 * TreeNode *right;
8 * TreeNode(int x) : val(x), left(NULL), right(NULL) {}
9 * };
10 */
11 class Solution {
12 public:
13 int maxDepth(TreeNode*
root) {
14
15 if(root==
NULL)
16 return 0;
17 int l=maxDepth(root->
left);
18 int r=maxDepth(root->
right);
19
20 return l>r?l+
1:r+
1;
21 }
22 };
23
24
25
26 //非递归的宽度优先方法
27 /**
28 * Definition for a binary tree node.
29 * struct TreeNode {
30 * int val;
31 * TreeNode *left;
32 * TreeNode *right;
33 * TreeNode(int x) : val(x), left(NULL), right(NULL) {}
34 * };
35 */
36 class Solution {
37 public:
38 int maxDepth(TreeNode*
root) {
39
40 if(root==
NULL)
41 return 0;
42 queue<TreeNode *>
q;
43 q.push(root);
44 int nCount=
1;
45 int nDepth=
0;
46 while(!
q.empty())
47 {
48 TreeNode * temp=
q.front();
49 q.pop();
50 nCount--
;
51 if(temp->left!=
NULL)
52 q.push(temp->
left);
53 if(temp->right!=
NULL)
54 q.push(temp->
right);
55
56 if(nCount==
0)
57 {
58 nDepth+=
1;
59 nCount=
q.size();
60 }
61 }
62 return nDepth;
63 }
64 };
转载于:https://www.cnblogs.com/aguai1992/p/4620016.html
