LeetCode:Binary Tree Inorder Traversal

yao_hust_iAC

于 2014-10-24 18:59:17 发布

阅读量436

点赞数

CC 4.0 BY-SA版权

分类专栏： LeetCode 文章标签： leetcode algorithm

本文链接：https://blog.youkuaiyun.com/yao_wust/article/details/40431773

LeetCode 专栏收录该内容

89 篇文章

订阅专栏

本文介绍了一种使用栈实现二叉树中序遍历的方法，并提供了详细的代码示例。该方法适用于非递归解决方案。

问题描述：

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

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

return [1,3,2].

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

思路：借助栈来实现树的中序遍历。

代码：

vector<int> inorderTraversal(TreeNode * root)
{
    vector<int> inorderSequence;
    stack<TreeNode *> treeNodeStack;
    TreeNode * node = root;
    if(node == NULL)
        return inorderSequence;
    while(node != NULL || !treeNodeStack.empty())
    {
        while(node != NULL)
        {
            treeNodeStack.push(node);
            node = node->left;
        }
        node = treeNodeStack.top();
        treeNodeStack.pop();
        inorderSequence.push_back(node->val);
        node = node->right;
    }
}