计算平均分的程序 java

Question

I'm beginning in java and encountering a few issues. I need to write a program that calculates an average mark in java without using arrays (haven't seen that yet), so we need to prompt the user to enter 5 marks and then calculate the result. The first prompt works (asking the student for its full name), but then I receive an error message "Exception in thread "main" java.util.InputMismatchException".

    import java.util.Scanner;

public class Sphere {


    public static void main(String[] args) {
String studentName;
int mark1, mark2, mark3, mark4, mark5;
double averageMark;
Scanner keyboard = new Scanner(System.in);
System.out.println("Please enter your full name");
studentName = keyboard.next();


System.out.println("Please enter your first mark");
mark1 = keyboard.nextInt();
System.out.println("Please enter your second mark");
mark2 = keyboard.nextInt();
System.out.println("Please enter your third mark");
mark3 = keyboard.nextInt();
System.out.println("Please enter your fourth mark");
mark4 = keyboard.nextInt();
System.out.println("Please enter your last mark");
mark5 = keyboard.nextInt();

    
averageMark = (mark1 + mark2 + mark3 + mark4 + mark5) / 5.0 * 100.0;
System.out.println("The test average for " + studentName + "is " + averageMark);



    } //main ends here

} // Sphere ends here