Java 需要从一组用户'；s级

在我的java类中，我们开始编写方法，而不是将所有代码放在主方法中。习题集中的一个问题是“编写一个方法，询问用户所修课程的数量n。然后该方法将询问在这些课程中获得的n个分数并返回其平均值”。以下是我目前掌握的情况：

 import java.util.*;

    public class MethodPracticeSet2 
    {public static int average()
    {
    //Create new Scanner object
    Scanner sc=new Scanner(System.in);

    //Create divisor variable
    int divisor=0;

    //Ask user for their course
    System.out.println("How many courses are you currently in?");
    int course =sc.nextInt();
    for (int i=0; i<course; i++)
    {
        System.out.println("What are your grades for those courses?");
        int grades[]= new int[i];
        grades[i]=sc.nextInt();
        divisor= divisor+i;
    }
    System.out.println("Your average for these courses is "+divisor/course);
    return average();
    }

    public static void main(String[] args) 
    {
        int output=average();
        System.out.println(output);
    }

    }  

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任何帮助都会很好

首先，需要在循环之前声明数组。目前，您正在循环的每次迭代中创建一个新数组，这显然不是您想要做的；这也是您获得

ArrayIndexOutOfBoundsException

的原因，原因是当您使用

i

being

0

实例化数组时，您试图将数字存储到空数组中，因此出现异常

---

以下是声明数组的方式：

int grades[] = new int[course];

for (int i = 0; i < grades.length; i++)
{
    System.out.println("What are your grades for those courses?");
    grades[i] = sc.nextInt();
    divisor += 1;
}

试试这个：

public class MethodPracticeSet2 {
public static int average() {
    // Create new Scanner object
    Scanner sc = new Scanner(System.in);

    // Create divisor variable
    int divisor = 0;

    // Ask user for their course
    System.out.println("How many courses are you currently in?");
    int course = sc.nextInt();
    System.out.println("What are your grades for those courses?");
    int sum = 0;
    for (int i = 0; i < course; i++) {
        sum += sc.nextInt();
    }
    System.out.println("Your average for these courses is " + (float) sum / course);
    return average();
}

public static void main(String[] args) {
    int output = average();
    System.out.println(output);
}

公共类方法练习集2{
公共静态整数平均值（）{
//创建新的扫描仪对象
扫描仪sc=新的扫描仪（System.in）；
//创建除数变量
整数除数=0；
//向用户询问他们的课程
System.out.println（“你目前修了多少门课？”）；
int course=sc.nextInt（）；
你对这些课程的分数是多少；
整数和=0；
对于（int i=0；i

---

}

仅解决IndexOutOfBounds症状。对解决实际问题没有任何作用。顺便说一句：递归调用是OP的，这里没有介绍。请尝试使用正确的缩进。

int totalGrades = 0;

for(int grade : grades){
   totalGrades += grade;
}
System.out.println("Your average for these courses is "+totalGrades / divisor);
return totalGrades / divisor;

public class MethodPracticeSet2 {
public static int average() {
    // Create new Scanner object
    Scanner sc = new Scanner(System.in);

    // Create divisor variable
    int divisor = 0;

    // Ask user for their course
    System.out.println("How many courses are you currently in?");
    int course = sc.nextInt();
    System.out.println("What are your grades for those courses?");
    int sum = 0;
    for (int i = 0; i < course; i++) {
        sum += sc.nextInt();
    }
    System.out.println("Your average for these courses is " + (float) sum / course);
    return average();
}

public static void main(String[] args) {
    int output = average();
    System.out.println(output);
}