函数功能：输入某班学生期末考试三门课程成绩

函数参数：长整型数组num，存放学生学号

整型数组score，存放学生成绩

整型变量n，存放学生人数

-Function: Enter a class final exam three course grade

Function parameters: long integer array num store student student number

Integer array score, and storage of student achievement

Integer variable n to store the number of students