Announcements

• Keep routinely checking this space for any announcements.

Instructions

• You need to log in using the email and password given to you by the invigilator in a strip of paper.
• Once logged in, you should see a message saying “You are registered for this contest”.
• You can use the chat icon on the bottom-left corner of this page to ask queries. Try using Google Chrome if you are not able to see the chat icon on Firefox. Make sure to start by stating your roll number. Queries about the problem statements should be asked as a Yes or No question, this enables us to answer your question much quicker. We will usually respond with one of: "Yes", "No", "Answered in Task Description (Implicitly/Explicitly)" or "No Comment". If your question is ambiguous or not a Yes/No question, we may ask you to rephrase the question in a Yes/No form.
• This is the Main Contest page. Before 1:45 pm IST, you should be in the practice contest page (https://icpc.codedrills.io/contests/inoi-2025-practice), which is scheduled to end at 1:45 pm.
• In case you are facing any issues, please report to the invigilator immediately.
• Please use Chrome browser. Don't use Firefox.
• Language documentation of C++ is available at localhost.
• The language documentation, along with cppreference documentation, is also available here. You need to extract it, and go to /cppreference/reference/en/cpp.html for the cppreference. And go to /STL SGI/index.html for the STL SGI documentation.
• Refer time always from CodeDrills contest page only. System times might not be in proper sync. There can be upto 5 minutes gap in machine times.

About the Contest

• Indian National Olympiad in Informatics 2025 - Main round
• Students need to keep their admit cards along with them at all times.
• Writing implements are allowed. Cellphones and other electronic devices are not allowed.
• In case of any hardware or power glitches, inform the invigilator as soon as possible.
• Using multiple IDEs together may lead to slow system, system may hang or crash. Be careful while using heavy IDEs.
• Only allowed language is C++.
• Any participant found to be indulging in any form of malpractice will be immediately disqualified.

Our contest adheres to the IOI scoring rules. Here’s what you need to know:

Scoring

• The leaderboard and other users’ activity will not be visible to the participants.
• This Main contest (INOI 2025 Main) has three problems. Each problem is worth 100 points. The test data of each problem is divided into multiple subtasks, each worth a portion of the total points. In order to pass a subtask, your submitted program must solve every test case within that subtask correctly and within the time and memory limits.
• You will be awarded the points allocated to a subtask if at least one submission you make during the contest passes that subtask. You do not need to combine your solutions for multiple subtasks into a single submission.
• Please keep in mind that the subtasks are not necessarily arranged in increasing order of difficulty. We encourage you to try as many subtasks as possible.
• Your position in the final ranking is determined only by your total number of points. The number of submissions you make and the time at which you submit are not taken into consideration, even for tie-breaking purposes.
• During the contest, you can see your total score by clicking on the "Scoreboard" tab. You will not be able to see the scores of other contestants.

Submitting

• In order for your solution to be considered for grading, it must be submitted to the appropriate problem on Codedrills. You are allowed to submit as many times as you want and as frequently as you want.
• When you submit a program to a problem, it will automatically be run against all the subtasks in that problem. You will see the verdict for your submission for all subtasks. "Subtask ID 0" refers to the sample test cases included in the problem statement, and is not worth any points.
• All submissions might be re-evaluated after the contest, using more test data. Hence the evaluation results you get might not be final.

Judge Details

• The only language allowed is C++.
• While running, the default stack size is 100 MB.
• For compiling steps, the following limits apply - Time Limit: 20s, Memory Limit: 2 GiB, Executable file size limit: 25 MiB
• C++ programs must always return 0 from the main function. Excluding that may result in a RTE verdict being returned.