# Chatbot Context Window

*English translation by SOTA – AI Community of the Russian original. Organisers who would like this translation removed can email sota.ai.community@gmail.com.*

*Task 1 of the school stage of the All-Russian School Olympiad (VsOSh) 2025/26 in artificial intelligence (region group IV), grades 9–11. The official answer and solution are in a separate file.*

A chatbot — a program that reads text and writes answers — can process at most 128000 conventional units of text at a time. Assume that one word is one conventional unit. An ongoing conversation already stores a history of 500 words. You want to upload a document in which every page contains exactly 400 words. The system's answer must be equal in length to the source text; the intermediate reasoning amounts to 15% of the length of the source text. What is the largest document that can be processed so that the total number of conventional units (history + source text + reasoning + answer) does not exceed 128000? Give the answer in pages.

**Scoring criterion:** exact match of the answer — 12 points

**Maximum score for the task — 12**