Обсуждение @ 1285. Нитка в гиперкосмосе @ Timus Online Judge

Vladimir Yakovlev (USU) Problem 1285 "Thread in a Hyperspace" has been rejudged [2] // Задача 1285. Нитка в гиперкосмосе 30 апр 2018 01:04

New tests have been added to the problem which exploit a common mistake when using acos function. Hint: try to calculate acos(sqrt(3.0) * sqrt(3.0) - 4.0) in your programming language. 269 authors (58%) with accepted solutions have been challenged.

Anatoliy V Tomilov Re: Problem 1285 "Thread in a Hyperspace" has been rejudged [1] // Задача 1285. Нитка в гиперкосмосе 3 май 2018 17:14

Why is this a mistake?

How to modify the solution to avoid the mistake? Who knows?

Anatoliy V Tomilov Re: Problem 1285 "Thread in a Hyperspace" has been rejudged // Задача 1285. Нитка в гиперкосмосе 3 май 2018 17:24

OK, just need to add a clamp for acos' arg.

Обсуждение задачи 1285. Нитка в гиперкосмосе