# 11 - coin1 ## The Challenge Mommy, I wanna play a game! (if your network response time is too slow, try nc 0 9007 inside pwnable.kr server) Running at: nc pwnable.kr 9007 ## The Solution This is more of a mathematical riddle than a pwn challenge. Check out our solver script. To find the counterfeit coin we ask to check all the coins with a specific bit lit. If the weight is not divisable by 10 the we know the counterfeit coin contains that bit. This process is repeated over and over. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://nickbhe.gitbook.io/shikata-ga-nai/pwnable.kr/11-coin1.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.