I studied chemistry and biology best in high school, but after studying electronics in Tsinghua for three years, we didn't need these two courses at all. I have reason to believe that I will never balance a chemical equation in my life. In the words of many people, these two courses are the stepping stones to the college entrance examination. At that time, I couldn't understand why we needed to study these courses. I told you the following example, and you should understand. When I was a freshman, we had a compulsory course called Mechanical Drawing-the main content was to draw screws on drawings. We are in the department of electronics. Why did you draw this? Indeed, since that semester, we have not been exposed to relevant content. Many of our classmates were very dissatisfied at that time. Our dean told us a story to calm our anger. He once took a senior undergraduate to do graduation project (16 weeks). The topic he gave the student was to write an application for a new computer. The structure of this computer is neither Feng nor Feng. Neumann system is not Harvard system. The computer language it uses is completely unconventional. In the first week, the teacher first gave this classmate a related book for him to understand. After a week of hard work, I figured it out. This is the case from the second week to the eighth week. Programming starts from the ninth week to the fifteenth week. Write a paper in the last week. This classmate successfully completed the task. When he graduated, his tutor asked him, "What course did you use for your four-year graduation project, calculus?" "No" "Linear Algebra?" "No" "C language?" "No" "Microcomputer principle?" "No .. English at most, because programming is written in English." "What did you do in college for four years? The courses you study are useless. " This classmate is very stupid. But the teacher asked, "If you are a high school graduate, can you finish this project in 16 weeks?" "Obviously impossible." "That's right. What you have learned in four years of college is the ability to learn knowledge. You have to study every book I gave you four years ago for a semester, and now you can fully understand it in a week. "