Question

我为我的班制作了这个程序，但是当它运行时它只是随机排序名称而不是按数字顺序（升序）对它们进行排序。我不知道我是否有任何错误，但我猜这个问题出现在下面的“ifs”中：

import javax.swing.JOptionPane;
public class RaceOrderApp {

  public static void main(String[] args) {
  String racer1, racertime1str, racer2, racertime2str, racer3, racertime3str;
  int racerTime1, racerTime2, racerTime3;

  racer1 = JOptionPane.showInputDialog(null, "Enter the name of racer #1:" );
    if (racer1 == null || racer1.length() == 0) {
    JOptionPane.showMessageDialog(null, "You did not enter a name. The application will end.");
    System.exit(1);}

racertime1str = JOptionPane.showInputDialog(null, "Enter the time of " + racer1 + ":" );

    racerTime1 = Integer.parseInt(racertime1str);

    if (racerTime1 >= 15 || racerTime1 <= 100) {
        JOptionPane.showMessageDialog(null, "You did not enter a valid time. The application will end.");
        System.exit(1);}

racer2 = JOptionPane.showInputDialog(null, "Enter the name of racer #2:" );

    if (racer2 == null || racer2.length() == 0) {
        JOptionPane.showMessageDialog(null, "You did not enter a name. The application will end.");
        System.exit(1);}

racertime2str = JOptionPane.showInputDialog(null, "Enter the time of " + racer2 + ":" );

    racerTime2 = Integer.parseInt(racertime2str);

    if (racerTime2 >= 15 || racerTime2 <= 100) {
        JOptionPane.showMessageDialog(null, "You did not enter a valid time. The application will end.");
        System.exit(1);}

racer3 = JOptionPane.showInputDialog(null, "Enter the name of racer #3:" );

    if (racer3 == null || racer3.length() == 0) {
        JOptionPane.showMessageDialog(null, "You did not enter a name. The application will end.");
        System.exit(1);}

racertime3str = JOptionPane.showInputDialog(null, "Enter the time of " + racer3 + ":" );

    racerTime3 = Integer.parseInt(racertime3str);

    if (racerTime3 >= 15 || racerTime3 <= 100) {
        JOptionPane.showMessageDialog(null, "You did not enter a valid time. The application will end.");
        System.exit(1);}    

    String firstRacer = racer1 + " " + racerTime1;
    String secondRacer = racer2 + " " + racerTime2;
    String thirdRacer = racer3 + " " + racerTime3;

    if (racerTime1 > racerTime2) {
        String temp = firstRacer;
        firstRacer = secondRacer;
        secondRacer = temp;
    }

    if (racerTime2 > racerTime3) {
        String temp = secondRacer;
        secondRacer = thirdRacer;
        thirdRacer = temp;
    }

    if (racerTime1 > racerTime2 ) {
        String temp = firstRacer;
        firstRacer = secondRacer;
        secondRacer = temp; 
    }
    String mensaje="The order of the racers is:\n";
    mensaje += "1st. " + firstRacer + "\n";
    mensaje += "2nd. " + secondRacer + "\n";
    mensaje += "3rd. " + thirdRacer + "\n";
    JOptionPane.showMessageDialog(null, mensaje);   
  }

}

提前感谢任何可以提供帮助的人！

Answer 1

你遇到问题if statements (racerTime2 >= 15 || racerTime2 <= 100)标志有问题它表示如果大于15或小于100，则必须大于100或小于15：

if (racerTime2 <= 15 || racerTime2 >= 100)

由于您未使用if statements或;

，所有else应以else if结尾

根据用户输入（名称和运行时间）对应用程序进行排序，并按数字升序排序

1 个答案: