初学Java if选择语句

import java.util.Scanner;

public class SubtractionQuiz {
  public static void main(String[] agrs) {
    int number1 = (int)(Math.random() * 100);
    int number2 = (int)(Math.random() * 100);
        
    if (number1 < number2) {
        int temp = number1;
        number1 = number2;
        number2 = temp;
    }
    
    System.out.print("What is " + number1 + " - " + number2 + "?");
    Scanner input = new Scanner(System.in);
    int answer = input.nextInt();
    
    if (number1 - number2 == answer) 
        System.out.println("You are correct!");
    else
        System.out.println("You are wrong
" + number1 + " - " + number2 + " should be " + (number1 - number2));
    
  }
}