Uploaded November 2020 | Updated September 2026, 3 weeks ago

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How to test a problem in polygon.codeforces.com/. This is how a testing process should look like.
Final problem: codeforces.com/gym/102873/problem/A
1-hour follow-up talk with authors: youtu.be/KnMOEiySz0Y
Testing of other problems: youtu.be/I7AJtUcVoxw

0:00 Intro
0:28 Statement
2:16 Sample Explanation
2:34 Issues
3:20 Solution
4:44 Wrong Solutions
7:06 Invocation
10:02 Tests
13:40 Generator
17:24 Validator
20:30 Validator Tests
23:17 Commit Changes

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