What interesting pits or circles have you had?

Fall into the pit of mathematical modeling. How can I put it? Mathematical modeling is quite big, and I haven't figured it out yet. After all, there are really many model algorithms. But in fact, in mathematical modeling, personally, it is not a simple model or algorithm, but a logical relationship. I am a person who transferred from electrical engineering to business school. From the most traditional engineering to the present business school, we use different knowledge points in everything we do. Logical relationship is the thing that can best reflect a person's level. Of course, I'm a vegetable. I'm practicing ing. Therefore, if a younger brother or sister happens to see it, I strongly recommend taking part in the mathematical model contest. It's not that you can prove how good your math ability is after you take part in it, but that you will learn how to solve a real and specific problem in the process.