[LeetCode]145.Binary Tree Postorder Traversal
来源:互联网 发布:网络市场结构特征分析 编辑:程序博客网 时间:2024/06/10 15:56
【题目】
Given a binary tree, return the postorder traversal of its nodes' values.
For example:
Given binary tree {1,#,2,3}
,
1 \ 2 / 3
return [3,2,1]
.
【代码】
/********************************** 日期:2014-12-07* 作者:SJF0115* 题号: 145.Binary Tree Postorder Traversal* 来源:https://oj.leetcode.com/problems/binary-tree-postorder-traversal/* 结果:AC* 来源:LeetCode* 总结:**********************************/#include <iostream>#include <malloc.h>#include <vector>#include <stack>using namespace std;struct TreeNode { int val; TreeNode *left; TreeNode *right; TreeNode(int x) : val(x), left(NULL), right(NULL) {}};class Solution {public: vector<int> postorderTraversal(TreeNode *root) { vector<int> v; stack<TreeNode *> stack; TreeNode *p = root; TreeNode *q; do{ //遍历左子树 while(p != NULL){ stack.push(p); p = p->left; } q = NULL; while(!stack.empty()){ p = stack.top(); stack.pop(); // 右子树是否为空或者已访问过 if(p->right == q){ v.push_back(p->val); //保留访问过的节点 q = p; } else{ //当前节点不能访问,p节点重新入栈 stack.push(p); //处理右子树 p = p->right; break; }//if }//while }while(!stack.empty());//while return v; }};//按先序序列创建二叉树int CreateBTree(TreeNode* &T){ char data; //按先序次序输入二叉树中结点的值(一个字符),‘#’表示空树 cin>>data; if(data == '#'){ T = NULL; } else{ T = (TreeNode*)malloc(sizeof(TreeNode)); //生成根结点 T->val = data-'0'; //构造左子树 CreateBTree(T->left); //构造右子树 CreateBTree(T->right); } return 0;}int main() { Solution solution; TreeNode* root(0); CreateBTree(root); vector<int> v = solution.postorderTraversal(root); for(int i = 0;i < v.size();i++){ cout<<v[i]<<endl; }}
【代码二】
/*------------------------------------------------* 日期:2015-03-25* 作者:SJF0115* 题目: 145.Binary Tree Postorder Traversal* 来源:https://oj.leetcode.com/problems/binary-tree-postorder-traversal/* 结果:AC* 来源:LeetCode* 博客:------------------------------------------------------*/#include <iostream>#include <stack>#include <vector>using namespace std;// 二叉树节点结构struct TreeNode{ int val; TreeNode *left; TreeNode *right; TreeNode(int x):val(x),left(nullptr),right(nullptr){}};class Solution {public: vector<int> postorderTraversal(TreeNode *root) { vector<int> result; if(root == nullptr){ return result; }//if stack<TreeNode*> s; s.push(root); TreeNode *node; while(!s.empty()){ node = s.top(); s.pop(); result.insert(result.begin(),node->val); // 左子树 if(node->left){ s.push(node->left); }//if // 右子树 if(node->right){ s.push(node->right); }//if }//while return result; }};// 1.创建二叉树void CreateTree(TreeNode* &root){ int val; //按先序次序输入二叉树中结点的值,‘-1’表示空树 cin>>val; // 空节点 if(val == -1){ root = nullptr; return; }//if root = new TreeNode(val); //构造左子树 CreateTree(root->left); //构造右子树 CreateTree(root->right);}int main() { freopen("C:\\Users\\Administrator\\Desktop\\c++.txt", "r", stdin); TreeNode* root = nullptr; vector<int> result; // 创建二叉树 CreateTree(root); Solution solution; result = solution.postorderTraversal(root); for(int i = 0;i < result.size();++i){ cout<<result[i]<<" "; } cout<<endl; return 0;}
1 0
- [LeetCode]145.Binary Tree Postorder Traversal
- [leetcode] 145.Binary Tree Postorder Traversal
- 145. Binary Tree Postorder Traversal LeetCode
- Leetcode 145. Binary Tree Postorder Traversal
- [LeetCode]145. Binary Tree Postorder Traversal
- Leetcode 145. Binary Tree Postorder Traversal
- leetcode 145. Binary Tree Postorder Traversal
- LeetCode 145. Binary Tree Postorder Traversal
- LeetCode-145.Binary Tree Postorder Traversal
- [leetcode] 145. Binary Tree Postorder Traversal
- LeetCode 145. Binary Tree Postorder Traversal
- leetcode 145. Binary Tree Postorder Traversal
- [LeetCode]problem 145. Binary Tree Postorder Traversal
- Leetcode 145. Binary Tree Postorder Traversal
- [LeetCode] 145. Binary Tree Postorder Traversal
- LeetCode 145. Binary Tree Postorder Traversal
- LeetCode 145. Binary Tree Postorder Traversal
- LeetCode:145. Binary Tree Postorder Traversal
- H264语法及结构(2)
- 使eclipse和java-docs-api中文文档无缝连接
- 为什么想到写博客
- Xcode中 工程全局宏与预处理 的配合使用
- Raft系列文章之一: 什么是Raft?
- [LeetCode]145.Binary Tree Postorder Traversal
- _exit和exit的区别?
- 【.NET机房重构】——注释新解
- handler looper 和 线程
- 使用指针实现字符串复制
- 整理一些ps4的DNS
- 取长补短
- 服务器×××上的MSDTC不可用解决办法
- OpenStack 网络项目(Neutron)的历史、现状与未来