I have Mac OS & Windows laptops. I use both of them quite frequently. Now I have an external hard drive that I want to use for both Mac & Windows laptops. Basically the flash drive should be able to transfer or copy/paste files from Windows laptop to MacOS. Or I should be able to … Read more
We will be solving LeetCode problem “129. Sum Root to Leaf Numbers” here. This is a common question which has been asked in interview rounds of Google & Microsoft. Problem definition is as follows: You are given the root of a binary tree containing digits from 0 to 9 only.Each root-to-leaf path in the tree … Read more
We will solve LeetCode problem “236. Lowest Common Ancestor of a Binary Tree” here. The problem states that: Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes p and q … Read more
Many of us use Collabedit frequently to conduct technical interviews. It is a easy to use online code editor where code can be shared between interviewer & interviewee. It supports most of the common programming languages available like Java, C++, Python, PHP or JavaScript. But recently I have seen Collabedit having server problems frequently. Sometimes the website … Read more
Here we will understand a common problem solving question from LeetCode. It is “239. Sliding Window Maximum”. You are given an array of integers nums, there is a sliding window of size k which is moving from the very left of the array to the very right. You can only see the k numbers in … Read more
Here we will try to find a solution for largest rectangle in histogram problem. We will use “LeetCode 84. Largest Rectangle in Histogram” problem as an example here. It says: Given an array of integers heights representing the histogram’s bar height where the width of each bar is 1, return the area of the largest … Read more
There are several ways to add code box in Blogger blog posts. Many of them would suggest to edit blogspot template and add third-party CSS links. But I prefer a way that doesn’t require any tampering or modification of blogspot template. First of all, it is risky & you may corrupt template HTML. Secondly, if … Read more
We will try to find all possible permutations of a given string. To understand this problem, we will use “LeetCode problem 47. Permutations II” and solve it. The problem states that: Given a collection of numbers, nums, that might contain duplicates, return all possible unique permutations in any order. Input: nums = [1,1,2] Output: [[1,1,2], … Read more
We are fond of one db session per request pattern. For web applications with JPA & Hibernate, it is good strategy in common cases. But for some long-running requests (definition of long-running depends on your use case, maybe 500 ms or 2 s), we need to tweak when we are actually acquiring a db connection … Read more
We will evaluate postfix expression here. Postfix expression is also called Reverse Polish Notation. This is a common LeetCode problem “150. Evaluate Reverse Polish Notation”. Let’s take an example & see how postfix expression works. Input: [“6”, “1”, “-“, “3”, “*”] Output: 15 Postfix means operator comes after the two operands. If you see the … Read more