Q6: Binary Tree Preorder Traversal

问题描述

Given a binary tree, return the preorder traversal of its nodes' values.

For example:
Given binary tree {1,#,2,3},

    \

    /

return [1,2,3].

Note: Recursive solution is trivial, could you do it iteratively?

解决原理

递归

代码

 /**

  * Definition for binary tree

  * struct TreeNode {

  *     int val;

  *     TreeNode *left;

  *     TreeNode *right;

  *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}

  * };

  */

 class Solution {

     vector<int> rst;

 public:

     vector<int> preorderTraversal(TreeNode *root) {

         if(root){

             rst.push_back(root->val);

             preorderTraversal(root->left);

             preorderTraversal(root->right);

         }

         return rst;

     }

 };

巴特西

Q6: Binary Tree Preorder Traversal

最新文章

热门文章