打印答题时间、正确题目数

/*What's 25-32 ? 556What's 34-13 ? 90What's 69-91 ? -22What's 66-86 ? 20What's 8-51 ? -43Correct count is: 2Test time is: 0 hour 8 minute 24 seconds25-32=556   wrong.34-13=90    wrong.69-91=-22   Right.66-86=20    wrong.8-51=-43    Right.*/import java.util.Scanner;public class SubtrationQuizloop {  public static void main (String[] args) {    long startSeconds = System.currentTimeMillis() / 1000;    Scanner input = new Scanner(System.in);    int correctCount = 0, answer;  //Count the number of the correct questions    final int NUMBER_OF_QUESTIONS = 5;    final int PER_SECONDS_MINUTE = 60;    String output = ""; // output string is initially empty    String isRight = "";    for (int count = 0; count < NUMBER_OF_QUESTIONS; count++) {      int number1 = (int)(Math.random() * 100);      int number2 = (int)(Math.random() * 100);      System.out.print("What's " + number1 + "-" + number2 + " ? ");      answer = input.nextInt();      if(number1 - number2 == answer) {          correctCount++;          isRight = "Right.";      }      else        isRight = "wrong.";      output += number1 + "-" + number2 + "=" + answer + "\t" + isRight + "\n";    }    long endSeconds = System.currentTimeMillis() / 1000;    int totalSeconds = (int)(endSeconds - startSeconds);    int seconds = totalSeconds % PER_SECONDS_MINUTE;    totalSeconds /= PER_SECONDS_MINUTE;    int minute = totalSeconds % PER_SECONDS_MINUTE;    int hour = totalSeconds / PER_SECONDS_MINUTE;    System.out.println("Correct count is: " + correctCount);    System.out.println("Test time is: " + hour + " hour " + minute + " minute "                        + seconds + " seconds");    System.out.println(output);  }}