/* Author: Jiangong SUN */ Here I will introduce the breadth first traversal of binary tree. The principe is that you traverse the binary tree level by level. This traversal is quite different than depth first traversal. In depth first traversal you…
Given a matrix of M x N elements (M rows, N columns), return all elements of the matrix in diagonal order as shown in the below image. Example: Input: [ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ] ] Output: [1,2,4,7,5,3,6,8,9] Explanation: Note: The total…
The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAPLSII…
We usually use the following 2 ways to traverse a dict: 1: for d in dic 2: for d in dic.keys() Which one is better? Let's have a look at one simple demo. #!/usr/bin/python dic = {'a': 1, 'b': 2, 'c': 1} print(dic) for d in dic: if dic[d] == 1: del(di…
https://leetcode.com/contest/weekly-contest-79/problems/binary-tree-pruning/ -- 814 from leetcode tree traverse (post traverse) left right and root the model void traverse(node){ if(node.left!=null) traverse(node.left); if(node.right!=null) traverse(…
Traverse an expression tree and extract parameters I think as you've said that using ExpressionVisitor works out to be a good approach. You don't need to implement all the Visit... methods as they already have a default implementation. From what I…
[LeetCode]498. Diagonal Traverse 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/diagonal-traverse/description/ 题目描述: Given a matrix of M x N elements (M rows, N columns), ret…
