Baltic Way 2019 · Problem 10
Combinatorics
There are 2019 points given in the plane. A child wants to draw (closed) discs in such a manner, that for any two distinct points there exists a disc that contains exactly one of these two points. What is the minimal , such that for any initial configuration of points it is possible to draw discs with the above property?
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Review
Topics
Pigeonhole and extremal arguments
Solutions
No verified local solution is currently available.
Contest context
Results from Baltic Way 2019
11 teams
- Mean score
- 1.6 / 5
- Scores of 4 or 5
- 2 / 11
- Estonia
- 0 / 5
Score distribution
06
10
21
32
40
52
All team scores
| Team | Score |
|---|---|
| St. Petersburg | 5 / 5 |
| Poland | 5 / 5 |
| Estonia | 0 / 5 |
| Lithuania | 2 / 5 |
| Germany | 3 / 5 |
| Norway | 0 / 5 |
| Finland | 3 / 5 |
| Denmark | 0 / 5 |
| Sweden | 0 / 5 |
| Latvia | 0 / 5 |
| Iceland | 0 / 5 |