Competition questions are different from basic questions, and basic questions can be done by ordinary people. It is necessary to work hard on the competition questions. My experience is to find some basic knowledge and questions to introduce the game first. After you have mastered the basic knowledge and methods of the competition, it will be much easier to do some difficult questions. Even if you can't do it, you should be able to understand the answer. Remember, you must do more and practice more. There is no shortcut. I have been there before.