Tools
ZAK's interactive tools, built for the Cambridge syllabus.
Not generic — every tool here maps to something you'll be asked to do in the exam.
cswithzak.com/tools — 30 labs
Tools tourProgramming & algorithms
Write it, run it, trace it — Paper 2 and Paper 4 skills in the browser.
Pseudocode Playground
Write CAIE pseudocode, press run, see the output. Errors point to the exact line.
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Python Playground
Real Python 3 in your browser — input(), files, classes, exceptions — with a trace table and the Python twin of every pseudocode example.
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SQL Lab
Query a ready-made school database: SELECT, JOIN, GROUP BY, INSERT, CREATE TABLE — with real keys and referential integrity.
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Assembler & CPU Simulator
A real two-pass assembler that checks every mnemonic, operand and label, then steps through an animated fetch–decode–execute cycle with the exam trace table.
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Declarative Lab (Prolog)
Facts, rules and queries with every answer, the resolution trace and the errors an A2 examiner would flag.
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Flowchart Studio
Draw flowcharts with the Cambridge symbols and run them; turn pseudocode into a flowchart and back; check your drawing against the answer. Structure charts and state diagrams too.
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Pseudocode Translator
One program, four languages: CAIE pseudocode into Python, VB.NET or Java — the three languages the papers accept — with every difference explained.
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Data Structures Playground
Stacks, linear and circular queues, linked lists with a free list, binary trees and hash tables — arrays plus pointers, one operation at a time, with the pseudocode for each.
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Algorithm Lab
Bubble and insertion sort pass by pass, linear and binary search with the low/high/mid table, a recursion call-stack tracer, Dijkstra and A* on your own graph, and a perceptron that learns.
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OOP Designer
Class diagram ⇄ code: describe classes, inheritance and containment and get the diagram plus skeleton code in pseudocode, Python, VB.NET or Java — or read the diagram from pseudocode.
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Trace Table Generator
Paste any algorithm and get the complete trace table — the exact skill Paper 2 tests.
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Theory labs
Paper 1 and Paper 3 topics you can actually operate: numbers, gates, networks, the CPU, the OS, the compiler.
Number Systems Lab
Binary ↔ denary ↔ hex ↔ two's complement, binary arithmetic, shifts and masks with the working, plus A2 floating point (mantissa + exponent, normalisation, ZAK's method) with every step of the working shown. Practice mode included.
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Data Lab
File-size calculations with the working, run-length and dictionary compression you can watch, lossy sliders, character codes, pixels and samples, and A2 file organisation.
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Networks Lab
Parity blocks and checksums, packet switching over routers, IP and subnet arithmetic, the URL-to-page journey, TCP/IP layers, RSA and the TLS handshake, and a blockchain you can break.
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Database Designer
Normalise to 3NF with every partial and transitive dependency checked, draw ER diagrams and resolve many-to-many, design a 2210 table with validation — then create it in the SQL Lab.
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Compiler Lab
Infix ⇄ Reverse Polish with the stack drawn at every step, RPN evaluation, BNF grammars tested with derivations and syntax diagrams, lexical analysis with a symbol table, parse trees and the four stages of compilation.
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Systems Lab
Fetch–decode–execute in register-transfer notation with the buses lit, interrupts on a timeline, control systems that run your pseudocode, OS scheduling and paging, pipelining.
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Logic Gates Lab
Type an expression and get the circuit and truth table — or draw the circuit with gates and read off its expression.
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Boolean Algebra & K-map Lab
Karnaugh maps with the optimal loops, sum-of-products, simplest form and every Boolean algebra law named — plus live adders and flip-flops, and past-paper practice marked like the mark scheme.
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Exam practice
Real questions, assignments, quizzes and full mock papers — marked.
Programming Tasks
Exam-style scenario tasks marked automatically against normal, boundary and abnormal test data — pseudocode or Python, hidden tests, model answers.
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Testing & Validation Lab
Normal / boundary / abnormal / extreme test data for any spec, validation rules on real inputs, check digits with the working, syntax vs logic vs run-time errors.
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ZAK Assignments
A full assignment for every topic, built by AskZ from ZAK's own class assignments — figures, model answers, mark scheme, self-marking and a PDF download. Three sets per topic.
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Topical Past Paper Questions
Every real Cambridge question since 2015 (plus the still-relevant ones back to 2010), filed by topic with its mark scheme and what the examiner said about it. Answer, reveal, self-mark — or let AskZ mark it like an examiner.
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Mock Paper
A full timed paper of real Cambridge questions drawn to the real topic weightings — mark yourself, see the score by topic, share a seed so a class sits the same paper.
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Statometer
Every topic measured against every real Cambridge paper: how often it is set, the odds it appears in your next paper, marks a paper, trend, command words and what inside it gets asked — ranked, and re-ordered by your own quiz record.
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Syllabus Map
Every topic × every year since 2015, coloured by how much of the paper it took, with command words and when it was last set — click through to the questions.
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Topic Quizzes
Auto-marked MCQs with an explanation for every answer. Earn XP.
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Study & organise
Notes, videos, flashcards and your exam timetable.
AskZ Smart Notes
Complete notes for every topic, written by AskZ from ZAK's material and the mark schemes — infographics, quiz, past papers inside; download as slides.
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Video Lectures
Every lecture, past-paper walkthrough and Zakathon revision session on ZAK's YouTube channel, indexed by syllabus topic — watch here, or from the topic page's Resources card.
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Flashcards
1,600+ shuffled cards across every topic of 2210 / 0478 and 9618. Flip, rate, drill your weak ones.
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Exam Timetable & Planner
Paper dates, sessions and Key Times for your Cambridge zone, a live countdown, calendar export and a week-by-week revision plan.
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