Checklist VsOSh AI 2026 Regional Stage, Tour 1 (mathematics) · G task
Segments
Russian title: Отрезки
Determine which counts in [1500, 2025] are achievable for the number of non-overlapping subsets of training runs when at most two runs overlap at any time.
The task
Training runs of equal duration are scheduled on a shared server; each run is a time interval, all endpoints are distinct, and at any moment at most two runs are in progress. Let A be the number of non-empty sets of runs that can be carried out without overlapping in time (for one run A = 1; for two overlapping runs A = 2; for two disjoint runs A = 3).
Which values from the interval [1500; 2025] can A take?
Abridged and translated by SOTA from the official Russian materials. The official statement has the exact rules, and it wins wherever this summary differs.
In English
This task was published in Russian. SOTA translated its 3 files into English on 16 September 2026. Only the words changed in the notebooks: markdown, code comments, messages and printed output. The code, file names and paths are the original's, so a translated notebook runs with the original data.
- Task statement Russian original of Task statement
- Full paper (all tasks of the tour) Russian original of Full paper (all tasks of the tour)
- Official editorial (all tasks of the tour) Russian original of Official editorial (all tasks of the tour)
Read the task statement in English
Segments
English translation by SOTA – AI Community of the Russian original. Organisers who would like this translation removed can email [email protected].
All-Russian School Olympiad in Informatics 2025–2026, Regional Stage, Grades 9–11
“Artificial Intelligence” profile, Tour 1, 17 January 2026
Task G
Points for the task: 50
Answer submission format: entering the answer
Number of attempts: 10
Submission that counts: the last one
Statement
Model training runs of equal duration are scheduled on a shared server. Each run is a time segment. All the endpoints of the segments are distinct. The administrator has configured the queue so that at any moment the server is busy with at most two such runs.
Let be the number of ways to choose a non-empty set of runs that can be carried out without overlapping in time.
For example:
- if there is one segment on the line, then ;
- if there are two intersecting segments, then ;
- if there are two non-intersecting segments, then .
Which values from the segment can the quantity take?
Output format
As your answer, output all suitable values in ascending order, separated by spaces.
Scoring
An exact match of the answer: 50 points.
Test results are not available during the tour.
Translated by SOTA. The Russian original is the official version and wins wherever the two differ. The statement is translated from the tour's PDF paper; the official editorial is a single notebook covering all tasks of the tour. If you organise this olympiad and would like the translation removed, email [email protected] and we will take it down.
At a glance
- You get
- Statement only.
- You submit
- All suitable values in increasing order, separated by spaces.
- Scoring
- Answer entry; 50 points for an exact match; 10 attempts, the last one counts; results hidden during the tour.
- Rules
- Python may be used, or the problem may be solved purely mathematically.
- Format
- Regional stage, Tour 1, 17 January 2026; grades 9–11; individual; 300-minute tour (Moscow procedure); answers entered in Yandex Contest.