<!-- Notes: 🎉 Congrats on solving the challenge and we are happy to see you'd like to share your solutions! However, due to the increasing number of users, the issue pool would be filled by answers very quickly. Before you submit your solutions, please kindly search for similar solutions that may already be posted. You can "thumb up" on them or leave your comments on that issue. If you think you have a different solution, do not hesitate to create the issue and share it with others. Sharing some ideas or thoughts about how to solve this problem is greatly welcome! Thanks! --> ```ts // your answers type Includes<T extends readonly any[], U> = { [P in T[number]]: true }[U] extends true ? true : false; ```
