思考题 with hard-to-write checker and interactor Peripheral Lightup! Note: this is not a traditional problem. Follow the instruction in the statement to help construct your solution Lead-in: The Palace is celebrating a festival with LED lights! Ins……

Solved! Difficulty: Div2C 思考题 in dreamland Construct it XGN dreamt about the following problem when sleeping: You are given a positive integer n (2\leq n\leq 10^8). Output an arithmetic expression that yields the value n with the following……

思考题 which is an adaptation from a popular problem. The source problem is very popular. IDK if this adaptation has been made or not. Adaptation There are N people indexed from 1 to N in a room. Each of them is given a hat of a random color. The t……

Finally some geometry! Maybe very easy though. Currently I am undergoing the College Entrance Exam(GK) so I don't have many ideas for Competitive Programming problems. This problem is inspired by some math problem in GK Simulation. Of course, this ……

思考题 of Div2B-C Elevator Welcome back to OBCYSIO! Orange Boy has been promoted to LGM boy so this series is in an awkward situation. This problem is very easy. Consider an elevator with a max speed of v_m m/s and an acceleration of a m/s^2. When ……

anniversary 思考题 Very Easy Problem Wow! OBCYSIO has reached 50 episodes! Let's celebrate using a very popular and easy problem. Hikari and Ninetail are playing a game on an undirected graph of N nodes and M edges. They move in turns, with Hikari ……