题目描述
输入一棵二叉树，求该树的深度。从根结点到叶结点依次经过的结点（含根、叶结点）形成树的一条路径，最长路径的长度为树的深度。
解题思路
时间复杂度：${O(n)}$,空间复杂度：$O(1)$.
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/*
struct TreeNode {
int val;
struct TreeNode *left;
struct TreeNode *right;
TreeNode(int x) :
val(x), left(NULL), right(NULL) {
}
};*/
class Solution{
public:
int TreeDepth(TreeNode* pRoot)
{
int count_left = 0;
int count_right = 0;
if(pRoot == NULL) return 0;
if(pRoot->left != NULL) count_left += TreeDepth(pRoot->left);
if(pRoot->right != NULL) count_right += TreeDepth(pRoot->right);
return max(count_left, count_right)+1;
}
};
class Solution {
public:
int TreeDepth(TreeNode* pRoot)
{
if(pRoot == NULL) return 0;
return max(TreeDepth(pRoot->left), TreeDepth(pRoot->right))+1;
}
};
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