Do not confuse this advise with the official
If you are a first-time participant of an IOI,
either as a delegation leader or deputy, an observer, or a competitor,
then it is advisable to read some of the reports for
Every IOI is different, but the changes should not be very drastic (mostly).
Depending on where the olympiad is held,
from what area a delegation travels to the olympiad,
and which other countries are passed during the trip,
it may be necessary to apply for appropariate visa.
Visa applications can take a long time to process.
Make enquiries early.
The IOI Host can provide an official Letter of Invitation,
and sometimes also specific assistance for obtaining a visa.
Flight reservations, extra hotel days
Make flight reservations early.
There may be other events going on at the same time
that compete for seats.
If you arrive earlier (before the scheduled Arrival Day),
or depart later (after the scheduled Departure Day),
you will have to make your own hotel arrangements.
Often, but not always, the IOI Host can be of assistance.
For example, there might be a possibility to stay in the
same hotel at a reduced rate.
Insurance and Vaccinations
The International Committee of the IOI
supervises the preparations of each IOI.
About half a year before the actual olympiad,
they visit the site and inspect the preparations.
They pay special attention to
meals, sleeping accommodations, transportation, excursions,
meeting facilities, safety and security, etc.
In spite of all the precautions,
each delegation is advised to arrange for proper insurance,
to cover for unforeseen expenses during the trip to/from the olympiad
and during the olympiad itself, including unforeseen medical expenses.
At the olympiad, hundreds of people from all over the world
get together for a week of close cooperation.
You are advised to check the possible need for vaccinations.
Contact your local medical advisor.
One of the sensible things you can do to reduce the risk of infection
is to wash hands often:
at least 5 times a day, with soap.
It has become a custom at some Olympiads, including the IOI,
to exchange (small) gifts.
Some people like this, others don't.
Keep in mind that cultures vary as to their customs of gift giving and
Dilemmas abound: when to give your gifts,
whom to give a gift and whom not, how big a gift (size, value),
when to open a gift, what to do if you cannot take it back home because you
already have too much baggage (return it?,
quietly throw it away?, give it to someone else?),
what if you have no gift to give when you receive a gift, ...
At IOI, (small) gifts are part of the informal atmosphere.
At some other Olympiads, gift exchanges have been abolished.
IOI gift exchanges are not officially organized,
nor are they especially discouraged or encouraged.
not everyone is supposed to give a gift to everyone else.
Do whatever you feel like.
What to Bring
Other things to keep in mind:
- Bring business cards with your e-mail and WWW address.
- Bring (English versions) of your national informatics olympiad tasks and
- Do bring a gift for your guide,
the person who escorts your delegation for an entire week.
Note that there may be restrictions on what goods you are allowed
to bring into or take out of the area where the olympiad is hosted.
It may be advisable to register valuables (e.g. a laptop computer,
digital video camera, etc.) upon leaving your home country.
This can help avoid time-consuming discussions on your return trip.
Local Conditions: Weather, communications, currency
Each host will inform participants about local conditions,
such as expected weather conditions,
communication facilities (phone numbers, mobile phone coverage),
and local currency, etc.
Competing for Gold
Everyone at the IOI goes for gold (one would expect).
Talent is what counts most,
but there are some basic habits that may help.
- Study carefully the tasks and solutions of recent previous IOI competitions.
- Weaker competitors are also advised to practice on easier tasks.
- The Competition Rules specify
what items you can bring into the competition area and
the procedure for doing so.
- Setting up your development platform
(e.g. to accommodate a personal keyboard)
can only be done after the start signal.
Practice this during the Practice Competition.
- The ultimate penalty for misbehavior at an IOI is
See the Competition Rules for details.
- Task descriptions
- Read all the tasks descriptions
carefully and completely.
And then read them again.
- The official version of the task descriptions are written in English,
and these are binding.
- The translations are made by the delegation leaders/deputies.
They need not contain diagrams.
- Consult the official version for diagrams and numbers
(such as upper bounds on input values).
- All tasks are different. If you cannot solve all of them,
work on the one(s) where you can get the best results, and
ignore the other(s).
- Programming tasks impose constraints on available resources
Note that inefficient programs,
which do not satisfy all constraints under
all required conditions, can often still score some points,
by solving simpler cases within the specified constraints.
- Clarification requests
- Clarification requests may be phrased in your native language.
Your delegation leader/deputy will translate your request into English.
- There are only three answers possible to a clarification request:
`Yes', `No', and `No Comment'.
The answer will not be translated!
- Clarification requests may only be submitted during the first hour
of each competition day.
- When you ask for a clarification
make sure that it can be answered with Yes/No,
and that such an answer will be helpful to you.
- Completely useless `question':
I do not understand what `X' means.
- Useless question:
Does `X' mean `A...' or `B...'?
- Useful question:
The definition of `X' in the task description seems ambiguous.
Does `X' mean `A...'?
- Input and Output Data
- You may assume that the official input data,
used for the evaluation of your program,
agrees with the task description.
That is, the (secret) test data will have the promised format and
all values will be within the stated bounds.
- However, no such guarantee applies to any test input that you yourself
Carefully check your own input files.
You can do that by looking at the input files in an editor,
by writing and applying (!) a separate input validiation program,
or by extending your program with an input validation routine.
If you do the latter,
your program may write a warning message to the screen for invalid data.
During official testing, no warning messages will be generated.
If you opt for an input validation routine,
it must do no i/o if the input data is valid.
- You are also responsible for proper formatting of output data.
If the output format does not agree with the task description,
then you will score zero points.
- Computers may fail; also at the IOI.
Frequently make backups of your program source files.
- A facility will be provided for the purpose of making backups.
See the Competition Rules.
- Know the features of your preferred programming language:
how to do I/O, how to use a library, ...
- Know how to operate the software tools available at an IOI:
compiler, integrated development environment, editor, debugger;
and also the operating system: file manipulation, scripting, timing,
- Prepare yourself for the practice session,
so that you do not waste time deciding what experiments to do
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