为什么我的 Java 摩尔斯电码翻译器给了我错误的输出？

Question

我已经看到很多关于摩尔斯电码翻译器的问题，并查看了其中的许多问题，但在所有问题中，建议的答案都给了我相同的错误输出。代码背后的想法是能够使用数组将摩尔斯电码翻译成英语，反之亦然。我的代码如下：

import java.util.Scanner;
public static void main ( String [] args )
{

    String [] morse = { ".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..", ".---", "-.-", ".-..", "--", "-.", "-.", "---", ".--.", "--.-", ".-.", "...", "-", "..-", "...-", ".--", "-..-", "-.--", "--..", "-----", ".----", "..---", "...--", "....-", ".....", "-....", "--...", "---..", "----.", "|"};

    String [] english =  { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", " "};

    Scanner input = new Scanner ( System. in );
    System.out.println ( "Enter 1 to translate Morse Code to English or 2 to translate English to Morse Code:");
    int userChoice = input.nextInt();
    String translateMe;

    while (userChoice < 1 || userChoice > 2 ) // Ensures user enters a valid choice
    {
        System.out.println( "Not a valid entry. Enter 1 to translate Morse Code to English or 2 to translate English to Morse Code:");
        userChoice = input.nextInt();
    }

   if (userChoice == 1 )
    {
        System.out.println("Please enter a Morse Code statement to translate. Separate letters with spaces and words with a ' | '" );
        translateMe = input.next();

        String [] morseChar = translateMe.split(" ");

        for( int x = 0; x < morseChar.length; x++)
        {
            String letter = morseChar[ x ];
            for ( int index = 0; index < morse.length; index++ )
            {
                if(morse [ index ].equals(letter))
                {
                    System.out.print(english[ index ]); // Display character at matching index position of English array to show translation
                }
            }
        }

        }

    else
    {
        System.out.println("Please enter an English statement to translate:");
        translateMe = input.next();
        translateMe = translateMe.toLowerCase();

        String [] englishChar = translateMe.split("(?!^)");

        for ( int x = 0; x < englishChar.length; x++)
        {
            String letter = englishChar [ x ];

            for (int index = 0; index < english.length; index++)
            {
                if( english [index].equals( letter ))
                {
                    System.out.print(morse[index] + " "); // Display Morse Code array character at matching index position to show translation
                }

            }
        }

    }

}

}

我一直在用这个词

to be

及其对应的摩尔斯电码

- --- | -… .

作为测试短语。当我尝试用这个短语将英语翻译成摩尔斯电码时，我得到了

... -.s 和 n

作为输出。当我尝试将摩尔斯电码转换为英语时，我得到了

u

作为输出。我检查了我的两个字符串数组以确保morse[A] 和english[A] 位于相同的索引位置等等，这些都很好。我想不出还有什么会导致这个问题的。

编辑：知道我正在使用 IntelliJ IDEA 15 可能会有所帮助

Answer 1

由于您使用 Scanner，无法将莫尔斯语翻译成英语。你需要使用 nextLine() 如下：

if (userChoice == 1 )
{
    translateMe = input.nextLine();
    System.out.println("Please enter a Morse Code statement to translate. Separate letters with spaces and words with a ' | '" );
    translateMe = input.nextLine();

之后，它似乎翻译得很好，即使使用 split 命令。

输出：

[.-, -..., -.-.]
abc

输出 2：

Please enter a Morse Code statement to translate. Separate letters with spaces and words with a ' | '
- --- | -... .
[-, ---, |, -..., .]
to be

Answer 2

1. n ("-.") 的代码在您的数组中出现两次。
2. 最好将字符串转换为char[]。您必须将字母表从 String[] 更改为 char[]。
3. 这就是为什么我们有Map。

Answer 3

我无法理解你得到的输出——虽然我没有尝试运行它，但通过目测我看到了一个非常不同的结果。

不过，从根本上说，您的莫尔斯-英语翻译器匹配得太早了。您需要检查整个字符串。

编辑：现在没有什么明显的问题，您是否尝试过使用调试器单步执行它以查看实际发生的情况？

Answer 4

你从英文翻译中得到“s”和“n”的原因是因为如果我们检查单词“to”，字母表中“t”的前一个字母是“s”，而字母表中的前一个“o”是“n”，所以这让我相信那里有一个循环错误。此外，您使用的是“next()”而不是“nextLine()”，因此您不会解析您认为的内容。我想如果你使用“nextLine()”并修复你的循环，你就会拥有它。感谢提供完整的源代码！ :D

这是我的测试方法：

import java.util.Scanner;

公共类主{

public static void main ( String [] args )
{

    String [] morse = { ".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..", ".---", "-.-", ".-..", "--", "-.", "-.", "---", ".--.", "--.-", ".-.", "...", "-", "..-", "...-", ".--", "-..-", "-.--", "--..", "-----", ".----", "..---", "...--", "....-", ".....", "-....", "--...", "---..", "----.", "|"};

    String [] english =  { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", " "};

    Scanner input = new Scanner ( System. in );
    System.out.println ( "Enter 1 to translate Morse Code to English or 2 to translate English to Morse Code:");
    int userChoice = input.nextInt();
    String translateMe;

    while (userChoice < 1 || userChoice > 2 ) // Ensures user enters a valid choice
    {
        System.out.println( "Not a valid entry. Enter 1 to translate Morse Code to English or 2 to translate English to Morse Code:");
        userChoice = input.nextInt();
    }

    if (userChoice == 1 )
    {
        System.out.println("Please enter a Morse Code statement to translate. Separate letters with spaces and words with a ' | '" );
        translateMe = input.next();

        String [] morseChar = translateMe.split(" ");

        for( int x = 0; x < morseChar.length; x++)
        {
            System.out.println("Comparing " + morseChar + " to the morse array");
            for ( int index = 0; index < morse.length; index++ )
            {
                System.out.println("Comparing equality of: " + morseChar[x] + " and " + morse[index]);
                if(morseChar[x].equals(morse[index]))
                {
                    System.out.print(english[ index ]); // Display character at matching index position of English array to show translation
                }
            }
        }

    }

    else
    {
        System.out.println("Please enter an English statement to translate:");
        translateMe = input.next();
        translateMe = translateMe.toLowerCase();
        System.out.println(" Translating:  [" + translateMe + "]");

        System.out.println("Translating: " + translateMe);
        String[] englishChar = translateMe.split(" ");

        for(String s : englishChar) {
            System.out.println("Translation String: " + s);
        }

        for ( int x = 0; x < englishChar.length; x++)
        {
            System.out.println("Checking word: " + englishChar[x]);
            for (int index = 0; index < english.length; index++)
            {
                System.out.println("Comparing equality of: " + englishChar[x] + " and " + english[index] + " they are " + (englishChar [ x ].equals( english[index]) ? " equal" :  " not equal"));
                if( englishChar [ x ].equals( english[index]))
                {
                    System.out.print(morse[index] + " "); // Display Morse Code array character at matching index position to show translation
                }

            }
        }

    }

}

}