Greedy

Subtitle / Summary The greedy idea is not “buy low, sell high” as a slogan. The precise rule is: if today is the sell day, the best buy day must be the lowest price before today. Reading time: 8-10 min Tags: Hot100, greedy, array, stock SEO keywords: LeetCode 121, Best Time to Buy and Sell Stock, greedy, historical minimum price Meta description: A pressure-first Python guide to LeetCode 121 that derives brute force, historical minimum price, and the final one-pass greedy solution. Problem Requirement You are given an array prices, where prices[i] is the stock price on day i. ...

Subtitle / Summary Jump Game is not about guessing one path. It is about maintaining how far all reachable positions can cover. Reading time: 8-10 min Tags: Hot100, greedy, array, reachability SEO keywords: LeetCode 55, Jump Game, greedy, farthest reach, reachability Meta description: A pressure-first Python guide to LeetCode 55 that derives a reachable-array baseline and compresses it into the farthest reachable range. Problem Requirement You are given an integer array nums. ...

Subtitle / Summary Maximum Subarray is the classic 1D DP / greedy template. This ACERS guide explains Kadane’s idea, engineering use cases, and runnable multi-language solutions. Reading time: 10–12 min Tags: Hot100, dynamic programming, greedy SEO keywords: Maximum Subarray, Kadane, dynamic programming, O(n), Hot100 Meta description: Kadane O(n) maximum subarray sum with engineering scenarios and multi-language code. A — Algorithm Problem Restatement Given an integer array nums, find the contiguous subarray with the largest sum (must contain at least one element) and return the sum. ...

Subtitle / Summary A classic event-spacing validation model. This ACERS guide explains the one-pass logic, engineering use cases, and runnable multi-language solutions. Reading time: 10–12 min Tags: array, two pointers, event spacing SEO keywords: LeetCode 1437, event spacing, O(n) Meta description: One-pass validation for minimum spacing between 1s, with engineering use cases and multi-language code. A — Algorithm Problem Restatement Given an integer array nums and integer k, return true if every pair of 1s is at least k apart; otherwise return false. ...