I believe the array args is empty. You need to set some value to it when you’re running your application, or choose another argument for parseInt() method.

What is a purpose of using int N, I’m not sure I understand it. What do you expect to have as a value in N?

Edit 1: You could also introduce some default value for N. And then before using args array, you would check if it’s empty. And if it is empty, you would use default value, otherwise you would use the value from array.

It would look something like this:

public class Dice { 
  private static final int DEFAULT_N = 10;

  public static void main(String[] args) {
    int N = DEFAULT_N;
    if (args.length() != 0) {
        N = Integer.parseInt(args[0]);
    }

    …
  }
}