To consider the last question, we should first make good use of the answers to the first two questions. Generally speaking, the last few questions are the previous jumps and upgrades. Maybe you can't find your way of thinking at once, but you must pay attention to the transformation and make full use of your conclusions.
Generally speaking, the answer to this question is very smooth and simple, maybe just a few lines, but it has a great thinking capacity. At this time, we should pay attention to adjusting our thinking direction in time. Learning structure is a bit difficult, but it is very important.
For the Olympics, I think it is still useful. Beijing's last question does have a competitive style. But at ordinary times, I suggest that you just need to learn the important methods and ideas in the Olympic Mathematics, and you don't need to spend too much time. In this case, we will look at the problem from a certain height.
Of course, a final question may not be thought out by one person, and mentality is very important. All right, come on!