Coding Olympiad
Australian Informatics Olympiad (AIO) Preparation
To prepare for the Australian Informatics Olympiad, get genuinely fluent in one allowed language and then practise reading problems and chasing subtasks — the three-hour, six-problem paper uses subtask scoring worth 100 points per problem, so partial solutions earn real marks and a points-first strategy beats trying to fully solve everything. The AIO is a programming competition for Years 7–12 that requires writing and submitting working code, judged automatically against test data.
From your child’s result to a practical next step
Find the difficulty that sounds familiar. Choose one action, try it, and use fresh work to check progress.
An AIO solution works on small inputs but runs too slowly on large ones. How should a beginner investigate it?
Check correctness and growth in work separately. Passing small inputs does not prove that a program handles every case, and a slow large input may reveal an algorithmic bottleneck rather than a language problem.
Count repeated operations. A pair of loops over all n items can do roughly n² steps: increasing n tenfold can increase that work about a hundredfold. Compare this with the problem's constraints, identify duplicated work, and consider a suitable better method. Test again on both small cases with known answers and larger inputs.
What is the difference between a wrong-answer result and a time-limit result when practising AIO programming problems?
A wrong-answer result means the produced output did not match the expected answer for the tested case. A time-limit result means the program did not finish within the judge's allowed time; it does not establish that the answer would have been correct.
For wrong answers, inspect input handling, boundary cases and the reasoning. For a time limit, inspect loops, repeated calculations and possible non-termination. Keep a tiny case with a hand-checked answer while improving performance so a faster version does not silently become incorrect.
How can a student design boundary test cases before submitting an AIO program?
Build test cases from the limits and the rules in the problem statement. Include the smallest permitted input, equality boundaries, repeated values where allowed, and cases that change a decision.
For a task finding a maximum, try a one-item list, equal values, and a maximum at the beginning and end. If negative values are allowed, [-4, -2, -9] should produce -2, not 0. Write the expected answer before running the program. Do not add invalid inputs unless the task explicitly requires handling them.
How should a beginner balance learning one algorithm with attempting complete AIO-style problems?
Pair each new technique with a complete problem that needs it, then a mixed problem where the student must decide whether it fits. Avoid collecting algorithm names without using them.
After learning a running total, solve several range-sum examples by hand, implement a solution, and check boundaries. Later mix in a task where a running total is unnecessary. Ask the student to explain the choice, constraints and complexity. Keep the problem small enough that reading, coding and testing all happen in the same learning cycle.
How can tracing a program by hand help a student prepare for the Australian Informatics Olympiad?
Tracing means recording how variables change after each instruction. It helps a student connect what a program actually does with what they intended it to do.
For a loop summing [2, 5, 1], make a table with item and total: 2→2, 5→7, 1→8. Then trace a version that resets total inside the loop and explain why it fails. Use a short input and compare the trace with the program output before attempting a larger example.
Which course fits a Year 8 student who knows basic Python?
Check whether the student can independently read input, write a solution and test it. If syntax still blocks that workflow, inspect AIO Python Foundation. If coding basics are secure but the method is missing, inspect AIO Algorithms. Our course outlines and starter lessons let you check the level before paying; a completed syntax course alone is not evidence of algorithmic readiness.
Ace Achievers learning guidance · Updated 5 October 2026. Examples are illustrative, not student results or promises of an award. Course choice and official exam eligibility are separate.
Choose the first training task by what your child can do
Use a complete, independently written program as the starting check. Knowing Python syntax is useful; AIO practice also needs correct input/output, test cases and an explanation of the algorithm.
AIO preparation decisions| Observation | Next task | Course to inspect |
|---|
| Cannot yet read numbers and print a computed result reliably | Write a short program from a plain-English rule; test zero, one item and repeated values. | Python Foundation |
|---|
| Can implement a simple solution; unsure why it times out | Count how the main loop grows as the input doubles; compare a more efficient method. | AIO Algorithms |
|---|
| Can explain standard methods and implement them unaided | Attempt a harder unseen problem, then review the proof and complexity before another timed set. | AIO Advanced |
|---|
AMT lists Python 3 among the allowed AIO languages. Changing language does not repair an unsuitable algorithm. The 2026 contest date has passed; use the organiser’s next published arrangements before making an entry plan.
Explore the complete AIO training curriculum →
Reviewed 3 October 2026. AMT AIO format and allowed languages. Worked examples and suggested routines are Ace Achievers guidance; they are not official entry or placement rules.
Key facts at a glance
- 2026 date: Thursday 27 August 2026; entries closed Friday 21 August 2026.
- Format: three-hour online exam, six problems of increasing difficulty.
- Scoring: each problem has subtasks totalling 100 points; partial credit applies.
- Languages: C, C++, Java or Python 3; source code is auto-judged.
- Year levels: Years 7–12.
- Entry: through your school.
- Official source: Australian Informatics Olympiad / Australian Maths Trust.
- Dates & format: see the AIO dates and format page.
What the AIO actually requires
The AIO is not a pen-and-paper logic test — it is a coding contest. You read a problem, design an algorithm, write a program, and submit it to an automatic judge that runs it against hidden test cases. Because each problem is split into subtasks (for example, a version with small inputs worth partial points, then larger inputs worth the rest), you do not need to fully solve a problem to score. The single most important strategic habit is to bank the easy subtasks across all six problems before grinding on a hard full solution.
The points-first strategy
Strong AIO performers rarely solve every problem perfectly. They read all six problems early, solve the easy first subtasks quickly — often a simple brute-force program is enough — and only then invest time in the harder subtasks where they have an idea. A beginner who confidently codes the first two problems and grabs early subtasks on the rest can score well. Chasing one perfect solution while ignoring free subtasks elsewhere is the classic mistake.
What to learn, in order
| Stage | Focus |
|---|
| Foundations | Fluent input/output, loops, arrays, functions in one language |
| Easy subtasks | Brute force, simulation, careful reading of constraints |
| Core techniques | Sorting, prefix sums, two pointers, greedy, basic recursion |
| Harder subtasks | Binary search, simple dynamic programming, graph traversal |
A practical training plan
- Pick one language and get fast. Python 3 is friendly for beginners; C++ is faster for large inputs. Be able to read input and print output without thinking.
- Train on ORAC. The Australian Maths Trust’s ORAC judge hosts past AIO problems with automatic marking — the best possible practice, with instant feedback.
- Do past AIO papers under time. Simulate the three hours and practise the read-all-then-bank-subtasks routine.
- Review every miss. When a subtask fails, find out whether it was the algorithm, an edge case, or a bug — debugging skill is half the contest.
Debugging: the half of the contest nobody trains
Most students spend their practice time learning algorithms and almost none learning to debug, yet a working program that scores beats an elegant idea that crashes. Under the AIO’s automatic judge, a single off-by-one error or an unhandled edge case can drop a whole subtask, so the ability to find and fix bugs quickly is worth as much as the ability to design the solution. Practise reading the constraints carefully (they tell you which subtasks a brute-force approach can reach), testing your program on the smallest and largest allowed inputs, and checking boundary cases such as zero, one, or maximum-sized data before submitting. A calm, systematic debugging routine — reproduce, isolate, fix, retest — turns near-misses into banked points and is one of the fastest ways to lift an AIO score without learning a single new algorithm.
How the AIO fits the bigger picture
The AIO is the entry exam to Australia’s informatics pathway, which leads through invitation-only contests toward the International Olympiad in Informatics. If you are still choosing between coding competitions, our AIO vs CAT comparison explains the difference between writing code and computational thinking, and the CAT preparation guide covers the no-code alternative. To understand how a strong AIO result leads onward, read our AIO qualification pathway guide. A free diagnostic can help confirm a student’s readiness for algorithmic work.
Format and dates reviewed 3 October 2026 against the Australian Informatics Olympiad and the Australian Maths Trust. Dates and rules change every year — always confirm with the AMT or your school before relying on a date.
Frequently asked questions
How do I prepare for the Australian Informatics Olympiad?
Get fluent in one allowed language, then practise reading problems and chasing subtasks on past AIO papers and the ORAC training judge. Master input/output, brute force for easy subtasks, and core techniques like sorting, prefix sums and greedy. Aim for partial credit on every problem.
What is the format of the AIO?
The AIO is a three-hour online exam of six problems of increasing difficulty. Each problem is split into subtasks worth a total of 100 points, so partial solutions earn marks. Problems may be attempted in any order.
What programming languages are allowed in the AIO?
C, C++, Java and Python 3. Students submit source code, which is judged automatically against test data, so coding experience is required.
When is the AIO in 2026?
The 2026 AIO took place on Thursday 27 August; entries closed on Friday 21 August. Entry is through your school, so confirm arrangements with the school.
Do I need coding experience to enter the AIO?
Yes. Unlike CAT, which tests computational thinking without code, the AIO requires you to write and submit working programs, so genuine programming fluency is needed first.
AIO last-week checklist — what to do in the final days before the paper.
Where to go next
The fastest route is past papers grouped by pattern — which is how these courses are built.
FoundationAIO Python Foundation
Best for
- Complete beginners to programming
- Want real competition Python, not toy snippets
CoreAIO Algorithms
Best for
- Can already code, stuck on Q2–Q3
- Needs the standard techniques
AdvancedAIO Advanced
Lessons
24 past-paper lessons
Best for
- Targeting the top of the AIO
- Wants every past-paper pattern drilled
Not sure which level fits? The
free 20-minute diagnostic pinpoints the exact gaps and tells you which course to start with. No sign-up needed.