通过new Scanner(System.in)创建一个Scanner，命令行输出

import java.util.Scanner;

public class MyDate{

public static void main(String[] args){
int sum=0;
Scanner mas = new Scanner(System.in);
System.out.print("请输入学生人数："+"\t");
int students=mas.nextInt();
int[]score=new int[students];

int temp=0;
for(int i=0;i<score.length;i++){
//Scanner in=new Scanner (System.in);
System.out.print("请输入学生成绩的值："+"\t");
score[i]=mas.nextInt();
sum+=score[i];
if(i==score.length-1){
temp=i+1;
}
}
System.out.println(temp+"个学生的平均成绩为："+sum/temp);

}

}