Listing 5.4, SubtractionQuizLoop.java, generates five random subtraction questions. Revise the program to generate ten random addition questions for two integers between 1 and 15. Display the correct count and test time.

Listing 5.4

1 import java.util.Scanner; 2 3 public class SubtractionQuizLoop { 4 public static void main(String[] args) { final int NUMBER_OF_QUESTIONS = 5; // Number of questions int correctCount = 0; // Count the number of correct answers int count = 0; // Count the number of questions long startTime = System.currentTimeMillis(); String output = " "; // output string is initially empty Scanner input = new Scanner (System.in); 10 11 12 13 while (count < NUMBER_OF_QUESTIONS) { // 1. Generate two random single-digit integers int numberl = (int) (Math.random () * 10); int number2 = (int)(Math.random () * 10); 14 15 16 // 2. If numberl < number2, swap numberl with number2 if (number1 < number2) { int temp = numberl; numberl = number2; number2 - temp; 17 18 19 20 21 22 23 // 3. Prompt the student to answer "What is numberl - number2?" System.out.print( "What is " + numberl + " - " + number2 + "? "); int answer = input.nextInt(); 24 25 26 27 28 // 4. Grade the answer and display the result if (numberl - number2 == answer) { System.out.prfintln("You are correct!"); correctCount+; // Increase the correct answer count 29 30 31 32 33 34 35 else System.out.printIn("Your answer is wrong. " + numberl + " - " + number2 + " should be " + (number1 - number2)); 36 37 38 // Increase the question count 39 40 count++; output += " " + numberl + "-" + number2 + "=" + answer + ((numberl - number2 == answer) ? " correct" : 41 42 wrong"); 43 44 45 46 long endTime = System.currentTimeMillis(); long testTime = endTime - startTime; 47 System.out.println("Correct count is " + correctCount + " Test time is " + testTime / 1000 + " seconds " + output); 48 49 50 51 } What is 9 - 2? 7 - Enter You are correct! What is 3 - 0? 3 -Enter You are correct! What is 3 - 2? 1 FEnter You are correct! What is 7 - 4? 4 PEnter Your answer is wrong. 7 - 4 should be 3 What is 7 - 5? 4 - Enter Your answer is wrong. 7 - 5 should be 2 Correct count is 3 Test time is 1021 seconds 9-2=7 correct 3-0=3 correct 3-2-1 correct 7-4=4 wrong 7-5=4 wrong