Question

这就是我所做的。我需要在我的代码中进行更正。无法理解为什么这不起作用。

public class NewClass2 {
  public static void main(String[] args) {
    Scanner obj = new Scanner(System.in);
    System.out.println("Enter name of first city: ");
    String s1 = obj.next();
    char x = s1.charAt(0);
    System.out.println("Enter name of second city: ");
    String s2 = obj.next();
    char y = s1.charAt(0);
    System.out.println("Enter name of third city: ");
    String s3 = obj.next();
    char z = s1.charAt(0);
    if (x<y && y<z)
    System.out.println("The three cities in alphabetical order are " + s1 + " "+ s2 + " " + s3);
    else if (y<x && x<z)
     System.out.println("The three cities in alphabetical order are " + s2+ " " + s1 + " " + s3);
    else if(z<x && x<y)
     System.out.println("The three cities in alphabetical order are " + s3 + " " + s1 + " " + s2);    
    else if (y<z && z<x)
     System.out.println("The three cities in alphabetical order are " + s2 + " " + s3 + " " + s1);
     else if (x<z && z<y)
     System.out.println("The three cities in alphabetical order are " + s1 + " " + s3 + " " + s2);
     else 
     System.out.println("The three cities in alphabetical order are " + s3 + " " + s2 + " " + s1);

}
}

希望得到所需的解决方案。

Answer 1

您始终将第一个输入与自身进行比较！

char y = s1.charAt(0);

应该是

char y = s2.charAt(0);

和

char z = s1.charAt(0);

应该是

char z = s3.charAt(0);

使用调试器可以帮助您理解这些问题。

Answer 2

我建议使用Java的in-build方法为您完成排序工作。您可以简单地将这些字符串添加到列表中并调用Collections.sort函数。

以下是它的工作代码：

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;

public class TestClass {

    public static void main(String[] args) {
        List<String> list = new ArrayList<String>();
        Scanner obj = new Scanner(System.in);
        System.out.println("Enter name of first city: ");
        String s1 = obj.next();
        list.add(s1);
        System.out.println("Enter name of second city: ");
        String s2 = obj.next();
        list.add(s2);
        System.out.println("Enter name of third city: ");
        String s3 = obj.next();
        list.add(s3);

        Collections.sort(list, String.CASE_INSENSITIVE_ORDER);
        System.out.println("The three cities in alphabetical order are - " + list);
    }

}

一个程序，它从用户获取两个字符串并按字母顺序排列，而不使用java中的数组和循环

2 个答案: