二叉樹的最大深度

摘要： maximum depth of binary tree 題目： Given a binary tree, find its maximum depth. The maximum depth is the number of nodes along the longest ...

• maximum depth of binary tree

• 題目：

  Given a binary 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.

• 題目大意：給定一棵二叉樹，找它的最大深度。最大深度指的是從根節點向下到最遠的葉子節點，沿著這條路徑走過所經過的節點的數目。
• 思路：遞迴左右子樹，左右子樹最深的子樹的高度加一，就是當前二叉樹的最大深度。

// Definition for binary tree
struct TreeNode {
int val;
TreeNode *left;
TreeNode *right;
TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};
class Solution {
public:
int maxDepth(TreeNode *root) {
// 需要填入的程式碼塊
if(root == NULL)return 0;
int leftLength = maxDepth(root->left);
int rightLength = maxDepth(root->right);
return leftLength > rightLength ? (leftLength+1) : (rightLength+1);
// 需要填入的程式碼塊
}
};

• 測試結果