Question

在给我上课时要解决的一个问题，我需要输入一个字符串，然后打印出该字符串中有多少个数字。单词被定义为仅包含字符a-z和A-Z。我不能使用split（）。

public static void main(String[] args)
{
    Scanner input = new Scanner(System.in);
    String sentence;
    String currentWord;
    int wordCount;
    int spacePos;
    int validChar;

    System.out.print("Please enter a sentence: \n");
    sentence = input.nextLine() + " ";
    spacePos = sentence.indexOf(" ");
    wordCount = 0;
    currentWord = sentence.substring(0, spacePos);
    validChar = 0;

    while(spacePos > -1)
        {
            for(int i = 0; i < currentWord.length(); i++)
                {
                    int j = currentWord.charAt(i);
                    if( j >= 'a' && j <= 'z' || j >= 'A' && j <= 'Z')
                        {
                            validChar++;
                        }
                }
            if( validChar == currentWord.length() )
                {
                    wordCount++;
                }
            currentWord = currentWord.substring(spacePos);
        }
    System.out.println("The number of words in this string is " + wordCount + "\n\n");
    input.close();
}
}

}

这是我到目前为止的内容，但我收到一个错误，说currentWord = currentWord.substring(spacePos);是

java.lang.StringIndexOutOfBoundsException：字符串索引超出范围：-5

编辑：我的问题不仅与错误有关，而且与逻辑有关，但我花了好几个小时在纸上并将其从头重写并解决了。这是我未使用.split()的更新代码。

public static void main(String[] args)
{
    Scanner input = new Scanner(System.in);
    String currentWord;
    String sentence;
    int spacePos;
    int wordCount;
    int validChar;

    System.out.print("Please enter a sentence: \n");
    sentence = input.nextLine() + " ";
    spacePos = sentence.indexOf(" "); 
    currentWord = sentence.substring(0, spacePos); 
    wordCount = 0;
    validChar = 0; 

    if( spacePos == 0 )
        {
            spacePos = 1;
        }//end of if
    for( int i = 0; i < sentence.length(); i++ )
        {
            //  VALIDATES IF A WORD IS A WORD
            for(int j = 0; j < currentWord.length(); j++)
                        {
                            if( currentWord.charAt(j) > 'a' && currentWord.charAt(j) < 'z'
                                || currentWord.charAt(j) > 'A' && currentWord.charAt(j) < 'Z')
                                {
                                    validChar++;
                                }//end of if
                            if( validChar == currentWord.length() )
                                {
                                    validChar = 0;
                                    wordCount++;
                                }//end of if
                        }//end of for
            // ROMOVES PREVIOUS WORD
            sentence = sentence.replace(currentWord + " ", "");
            currentWord = sentence.substring(0, spacePos);
            spacePos = sentence.indexOf(" ") + 1; 
        } //end of for
    System.out.println("\n\n FINAL WORD COUNT --->\t\t" + wordCount + "\n");
    input.close();
}

Answer 1

下面的逻辑应该对您有用，

public static void main(String[] args)
    {
        int wordCount=0;
        StringBuffer newDummy=new StringBuffer();

        String dummy = "1223fgfdfsdfhi sdfsdfh8678 df 435";

                for(int i = 0; i < dummy.length(); i++)
                    {
                        if (Character.isDigit(dummy.charAt(i)))
                        {
                            wordCount++;
                        }else{
                            newDummy.append(dummy.charAt(i));
                        }
                    }

        System.out.println("The number of words in this string is " + wordCount + "\n\n");
        System.out.println("new String-->"+newDummy);
    }

计算仅包含Java

1 个答案: