Algorithms HQ vs iCoder

A fun and didactic app to learn computer science algorithms! See how algorithms are working by watching an animation of their execution. Understand how data is manipulated as it is animated through an intuitive representation of its contents. Always know which line is executed in the pseudo-code, what are the values of the variables. Need to quickly refresh your memory? Just use the app as a quick reference on the main characteristics of each algorithm! Main features: - Execute a single instruction, or undo the previous one - Run, or rewind the algorithm until you decide to pause the execution - Adjust the speed of the animation - Best and worst case input data for sorting algorithms - Change the input data: size (up to 500), maximum value or data distribution (random, sorted, many duplicates, etc.) - For data structures, choose the next function to execute, or let a scenario choose for you, so you can see how the data structure evolves. - Landscape or portrait orientation This version contains the following algorithms: Linear Data Structures: - Linked Lists, including a view on memory - Queue - Stack Sorting algorithms: - Bubble Sort - Cocktail Sort - Gnome Sort - Insertion Sort - Quick Sort - Selection Sort More algorithms and more features are on the way!

Eight years. One mission: help you master algorithms without distractions. iCoder is a LeetCode practice app trusted since day one by learners preparing for technical interviews. Version 8.0 marks our 8th anniversary with a complete SwiftUI rebuild: faster, cleaner, and ready for iOS 16 and later. Still 1000+ classic problems, still offline, still no ad popups. WHY iCODER - Born for interview prep: company-tagged problems mirror what top firms often ask - Organized by difficulty, tags, and companies so you can drill weak spots - Offline-first: the library lives on your device; browse, quiz, and widgets work without Wi-Fi - Eight years of polish: now with a modern SwiftUI interface and rich widgets BROWSE AND SEARCH - Numbered list or compact grid with adjustable columns on iPhone and iPad - Filter by Easy, Medium, Hard, VIP, favorites, and learning status - Optional Favorites and Recently Viewed at the top of the Problems tab - Search by problem ID, title, content, tag, or company - Swipe and context menus for favorites and status CATEGORIES - Algorithm tags from arrays to dynamic programming - Company collections for targeted interview practice - Smooth flow from filters to detail PROBLEM DETAIL - Bilingual Chinese and English descriptions - Adjustable font size - Unlearned, Learned, and Mastered tracking - Toolbar favorites and solution links when online - Share a long image for notes or study groups - Previous and next problem navigation DAILY QUIZ AND REVIEW - Ten questions per day by difficulty, tag, or company - Today score, best score, and streak - Wrong Book with one-tap return to full problem detail - Reshuffle for extra practice the same day LEARNING TRACKING - Favorites and Recently Viewed lists in Settings - One-tap clear all recents - Stats for favorites, learned rate, and mastered rate WIDGETS (iOS 16 AND LATER) - Daily Problem, Difficulty Glance, Daily Quiz, Favorites, Wrong Book, Learning Progress, Company Spotlight - Lock Screen and StandBy compact layouts; deep-link into the app - On iOS 17 and later: shuffle from Daily Problem and Company Spotlight Home Screen widgets without opening the app - In-app Widget Guide with FAQ PERSONALIZATION - Sixteen accent colors; Light, Dark, or System - Widget backgrounds can match your theme - English, Simplified Chinese, Traditional Chinese, or Follow System - List or grid layout with custom column count SHORTCUTS - Up to four Home Screen quick actions on long-press - Deep links from widgets and shortcuts - iPad and Mac keyboard shortcuts SUPPORT - Rate, email feedback, share the app, tip the developer - More apps from the developer - Optional App Store update reminder OUR PROMISE SINCE YEAR ONE - No ad popups inside the app - Offline problem library - Your time is precious; we respect it Requires iOS 16.0 or later. Download iCoder 8.0 and celebrate eight years of practice with us.