输入学生的学号、数学成绩、英语成绩、物理成绩、运行后得到总成绩并从高到低排名，且算出平均分；加入查找功能，输入学号后，显示学生成绩。-Enter the student s student number, math scores, English grades, physical results, after running to get the total score and　high to low ranking, and calculate the average score　join the search function, enter the student number, show student performance.