P8653 [Lanqiao Cup 2017 National C] Split Exam Rooms (Fake Problem: Minimum Chromatic Number).

$n$ people are taking a special exam. To ensure fairness, any two people who know each other cannot be assigned to the same exam room. Find the minimum number of exam rooms needed to satisfy this condition.

The first line contains an integer $n(1

Output one integer on a single line, representing the minimum number of exam rooms.

Time limit: 1 second, 256M. Lanqiao Cup 2017, the 8th National Finals. Translated by ChatGPT 5