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Problem Overview You are given the root of a binary tree.You are allowed to split the tree into two subtrees by removing exactly one edge. The goal is to maximize the product of the sums of the two resulting subtrees. Since the result can be large, return the answer modulo 10⁹ + 7. Key Insight … Read more

Picking an AI model in 2026 feels a bit like hiring a new teammate. On paper, everyone “does writing and coding.” In real life, one teammate is a lightning-fast brainstormer, another is a careful planner who won’t stop until the job is done, and another is the one you hire because you need everything to … Read more

Problem Overview In LeetCode 1161 (Maximum Level Sum of a Binary Tree), you’re given the root of a binary tree. Your task is to find which level (1-indexed) has the maximum sum of node values. Important details Key Insight To compute the sum at each level, the most natural technique is: ✅ Level Order Traversal … Read more

Problem (rephrased) You’re given an n x n integer matrix. You may perform the following operation any number of times: Your goal is to maximize the sum of all elements in the matrix. Key Insight The operation flips the signs of exactly two adjacent cells. So, ignoring zeros for a moment: Why adjacency doesn’t really … Read more

When working with Large Language Models (LLMs), the way you format your data matters more than you might expect. Two formats often discussed are JSON and TOON. Both represent structured data, but they are designed for different audiences: This article explains the difference in plain English, with examples, and shows when to use each. What … Read more

At first glance, LeetCode 1970 looks intimidating. There’s a grid, flooding cells day by day, and somehow you’re supposed to figure out the last possible day you can still cross from the top to the bottom. If your first thought was “Do I simulate every day?” — you’re not alone.Let’s slow it down and solve … Read more

December Daily Challenge – Solution Article (Backtracking + Memoization) Problem recap You’re given: If two adjacent blocks are A and B in the current row, you may place C directly above them. You build the pyramid upward by repeatedly forming the next row: Return true if any valid pyramid can be built; otherwise return false. … Read more

Imagine you’re building a chatbot for your business. You want it to answer questions like: A standard large language model (LLM) can write beautifully… but it doesn’t automatically know your policies, your internal documentation, or your latest updates. Even worse, if you ask it anyway, it may confidently invent details (hallucinate). That’s where RAG (Retrieval‑Augmented … Read more

Why You Don’t Always Need a Framework Modern frontend frameworks like React, Vue, and Angular are powerful—but they also come with: For many everyday tools and utilities, this is overkill. If you want to build: …you can often do everything you need with vanilla JavaScript, a bit of HTML, and some basic styling. This approach … Read more