British Informatics Olympiad: A BIO Round 1 Guide

The British Informatics Olympiad is unusually accessible for a national computing olympiad, and the reason is one sentence in its rules: each question may be solved in any programming language.

Three questions, three hours, any language

The British Informatics Olympiad is the national computing competition for schools and colleges in Britain, founded in 1995. Round 1 is a three-hour paper with three questions, taken in school.

The access point that matters: each question may be solved on any type of computer and in any language. A student who writes Python competes on equal terms with one who writes C++. For a school whose students learned Python in their computing lessons, nobody is excluded by language choice.

Questions are supplemented by written problems, so the paper tests reasoning as well as implementation. A student who can argue clearly but implements slowly still has marks available to them.

Three questions is fewer than it sounds

An hour per question sounds generous until you see the structure. Each question comes in parts of rising difficulty, so one question can absorb a capable student for the full hour and still have parts remaining.

That shapes the correct strategy. A student should attempt the early parts of all three questions before committing to the hard parts of any one, because the early parts carry reliable marks reachable with careful work.

Students who work through in order frequently never reach question three at all, which is the most common avoidable loss on the paper and costs more than any algorithmic weakness.

Multi-part questions are one question

BIO questions are deliberately built so that an early part establishes something a later part needs — a routine to write, a pattern to notice, a small case to generalise from.

A student who treats the parts as three separate problems makes the last one considerably harder than intended. Reading the whole question before starting is a trained habit and it pays within the first practice paper.

What the paper actually rewards

Careful enumeration solves more BIO parts than students expect. Writing a correct brute-force solution quickly is often the right opening move, and recognising when it suffices frees the time the harder parts genuinely need.

Simulation — modelling a described process exactly and running it forward — is a recurring BIO style where the difficulty is precision rather than cleverness.

Recursion and backtracking handle the combinatorial parts that appear in most papers. Dynamic programming appears in the later parts of harder questions.

The written problems ask for counts, explanations or short proofs rather than programs, so counting carefully and arguing clearly are part of the examination rather than optional extras.

For schools: the easiest olympiad to administer

Three features make the British Informatics Olympiad unusually practical to run.

It is sat in school, so no travel and no external venue. The school chooses its own date within a published window — for the most recent cycle, any date between early December and late January — so it fits around an existing timetable rather than clearing a fixed national date.

And because any language is allowed, the supervising teacher does not need to be a programmer or to standardise the school on a particular language first.

Our BIO preparation course works past Round 1 papers under full three-hour conditions, reviewed for time allocation across the three questions as much as for correctness.

Who can enter, and what to do if you cannot

Students under 19 studying full-time at an establishment of Secondary or Further, but not Higher, Education in mainland Britain. Round 1 is genuinely open to Year 10 and 11 students, equivalent to Class 9 and 10.

Students outside Britain cannot enter the official British Informatics Olympiad. The past papers remain excellent training for any computing olympiad, and we use them with students preparing for INOI and USACO precisely because the any-language rule makes them usable by students who have not yet learned C++.

Where it leads

Strong Round 1 performers are invited to the final round, from which the UK team for the International Olympiad in Informatics is selected.

For students on other national routes, BIO sits naturally alongside the Canadian Computing Competition and the Australian Informatics Olympiad, both of which are open to international schools and test overlapping skills in different formats.

In the UK, students who have not yet reached BIO level should look at Bebras, where a top 10 per cent finish earns an invitation to the Oxford University Computing Challenge — the natural bridge between computational thinking and full programming contests.

Preparing without a specialist teacher

Most schools entering the British Informatics Olympiad do not have a teacher who competes in programming contests, and they do not need one.

The past papers are published with solutions, which means a student can mark their own work and a supervising teacher only needs to hold the timetable. That is a genuinely low bar compared with olympiads requiring expert coaching, and it is why the British Informatics Olympiad reaches schools that enter nothing else.

What a teacher can usefully do is insist on the three-hour condition. A student who sits one full paper properly timed learns more about the British Informatics Olympiad than one who works through six papers at leisure, because the binding constraint on the day is time allocation rather than knowledge.

A note on preparation time

A student who already programs can prepare for Round 1 in a term. The work is not learning new syntax; it is learning to allocate three hours across three multi-part questions and to recognise when brute force is enough.

A student who does not yet program needs considerably longer, and should start with reasoning contests rather than attempting BIO cold. Dates, eligibility and the registration window are set each year, so check olympiad.org.uk for the current cycle.