The IMO 2015 contest will be held in Lotus Pang Suankaew hotel, Chiang Mai, Thailand. The contest takes place on Friday and Saturday, 10 and 11 July 2015.The contest is scheduled to start at 9.00 am and lasts 4 hours 30 minutes. Each day, students are given three problems in up to two languages of their choice.

Contestants may bring their personal writing and drawing instruments such as pens, pencils, erasers, pencil sharpeners, rulers and compasses into the examination room. You will need pens, pencils and erasers, a ruler and a compass. Not permitted are calculators (including watches with built-in calculators), mobile phones, electronic devices, protractors of any kind including set squares with protractor markings, briefcases, backpacks, toys, books, notes, tables, papers or any other written material. You may also bring your personal food or drinks (provided they do not make noise when consumed) and, if necessary, a small talisman (small enough so as to fit into one hand). Any personal utensils that you wish to bring into the contest room should be inside the transparent plastic bag that is given to you on arrival at the hotel.
By following this link: Important contest information, you can also find what is and what isn't allowed to bring to the contest.

The workplaces for all contestants are set up in one hall with 6 blocks. Each workplace has a code of three values in the order of one digit number, one alphabet, two digits numbers, for example, 3F11. The first one digit of number refers to the block number, the alphabet refers to the column and the last two digits refers to the row of each blocks. For example, the code 3F11 is the location of block 3, column F and row 11. On the back side of your badge you will find the code of your workplace. There are 6 entrances with block numbers indicated. All contestants are required to enter and exit from their entrances according to their assigned block number ONLY. Inside the hall, the invigilators will help to find your workplace. Find your workplace and remain seated quietly. Remain seated until after the exam. If you want to leave your seat because you need to go to the toilet, or because you want to finish the contest early, you must first consult the invigilators (use the green or red cards as described below). Follow this link: How to find your way in the contest halls, to find your way in the contest halls.
Please check that your workplace and the folder on your desk are indeed marked with your name and your contestant code.
Do not open the folder before you are instructed to do so.

On your workplace, you will find:
1. In a closed envelop: the contest problems in up to two languages as previously requested;
2. The contest folder which contain the following materials:
    2.1 An instruction sheet;
    2.2 Twenty (20) sheets of paper (Answer forms) to do your work;
    2.3 Three sheets of paper (Question forms) for submitting a question to the jury;
    2.4 Three problem folders with specific problem’s number printed on: Problem 1, 2, 3 for day 1, and 4, 5, 6 for day 2. Each folder is to collect solution sheets for ONE problem;
3. Five colored cards:
    • White: to request more papers;
    • Orange: to submit a question to the jury (during initial 30 minutes only);
    • Blue: to request water;
    • Green: if you need to go to the toilet;
    • Red: if you need help or want to stop working early (not during last 30 minutes)

The following announcements or communications will be made during the contest.
    • Before the contest: announcement “Remain seated quietly and do not open the contest folders before you are told to do so”.
    • At 0 hours 00 minutes working time: announcement “You may now open the folders, open the cover with the problems and start to work”.
    • After 0 hours 25 minutes: it will be signaled that you have five minutes left to ask questions to the jury (no announcement).
    • After 4 hours 00 minutes: it will be signaled that you have thirty minutes left for solutions. You may no longer leave the room.
    • After 4 hours 25 minutes: it will be signaled that you have five minutes left to work on the problems.
    • After 4 hours 30 minutes: announcement “Please stop working immediately. Put your solution sheets into the respective problem folders, sorted by problem, and all three solution folders into the large folder. Please remain seated until you are requested to leave the room”.
During the contest the elapsed time will be visible throughout the contest hall.

Writing your solutions

Write your solutions and rough work on the answer forms. You can get more paper if necessary (white card). Do not write on the back of the paper. Fill in your name, contestant code, problem number (so only one problem on a sheet of paper!) and page number on each answer form as you use it. You must work on your own and submit your solutions in your own language. Your work will be scanned and copied in black and white, so please use blue or black ink or a very dark black pencil.
In case you need more paper, please show your white card. An invigilator will give you five (5) more sheets of paper.

Questions to the jury

During the first 30 minutes of the contest, you may submit written questions to the jury. These should be written in your own language on the question form provided. Once your question is ready, raise your orange card and an invigilator will collect it and send it to the jury. The jury will decide whether the question will be answered, and if so, how; afterwards the answer will be communicated back to you. Depending on the number of questions, this may take some time.

Other needs or requests

If you need more water, raise your blue card. In case you have to go to the toilet, show your green card (not during the last 30 minutes of the contest). For leaving and returning into the hall there will be a check-out and check-in procedure. (Details will be added later.) In case of emergency or illness raise your red card to receive help.

At the end of the exam

Once the end of the examination is announced, stop writing immediately. Sort your work by problem number and put the solutions for each problem into the appropriate problem folder. Put the three problem folders, and only those, inside the large folder. Leave the large folder closed on your table and remain silent and seated until the invigilators have collected all the folders.
Do not put any blank sheet inside the problem folders. Unused blank sheets should be left on the table. Used paper that you do not want to submit should also be left on the table and will be discarded.
For more information on what to do at the end of your exam, please follow this link: How to submit your work.

Early termination of the contest

In case you finish your work during the first four hours (before the last 30 minutes are announced) you may show your red HELP card to tell the invigilators that you have finished and you want to leave the room. After leaving the examination room you will not be allowed to return to it. During the last 30 minutes you cannot leave the contest room before the regular work period is over; if you finish during this period, wait quietly in your place until the end. Also, you will not be allowed to leave the room during the first 30 minutes.

What to take out of the room

You are allowed to take the contest problems with you. Apart from this, you are allowed to take out of the room only the materials that you brought in your plastic bag. Specifically, do not take with you any blank or written answer sheet, query form or colored card.

Improper behavior

In the interest of a successful IMO 2015, contestants are expected to work quietly without disturbing others, and of course respect the obligation to work on their own. They need to follow these instructions and rules. In case of violations, the Chief Invigilator may issue warning, report incidents to the jury for further action, or take other suitable action to maintain the integrity of the competition.

The organizers of the IMO 2015 wish you good luck!
Invigilator coordinator: Dr. Pradthana Jaipong, pradthana@cmu.ac.th