java - 使用 while 循环删除字符，直到达到计数，Java 不工作

Question

我试图在循环中执行此操作，从字符串中删除元音，直到达到正确的字符数(140)，但是它不起作用。我不确定 do while 循环是否正在工作，然后在满足条件后停止，但如果是这种情况，一旦满足条件，我如何运行其余的代码？提前致谢!这是我正在使用的代码:

public static void main(String[] args)
{
    Scanner scan = new Scanner( System.in );
    System.out.println("Enter the phrase to be shortened: ");
    String toCompress = scan.nextLine();
    int length = toCompress.length();
    System.out.println(length);;

    do {
        toCompress = toCompress.replaceAll("[AEIOUaeiou]", "");
    }while(length >= 140);


    System.out.println("Compressed phrase: ");
    System.out.println(toCompress);
    int length2 = toCompress.length();
    System.out.print(length2);; 
    scan.close();

}

Answer 1

您需要一次删除一个元音，直到达到 140 长度。现在，执行 toCompress = tocompress.replaceAll("[AEIOUaeiou]", "") 后，您不会更新长度正确做法:

public static void main(String[] args){
    Scanner scan = new Scanner( System.in );
    String[] vow={"A","a","O","o","E","e","U","u","I","i"};
    List<String> vowels=Arrays.asList(vow);
    System.out.println("Enter the phrase to be shortened: ");
    String toCompress = scan.nextLine();
    int length = toCompress.length();
    System.out.println(length);

    String compressed="";

    while(length >= 140&&compressed.length()<140){
        String firstLetter=toCompress.substring(0,1);
        //if the first letter is not a vowel, add it to the compressed string
        if(!vowels.contains(firstLetter)) compressed.concat(firstLetter);   
        //remove the first letter from toCompress
        toCompress=toCompress.substring(1);
        //update the length to the new value
        length=compressed.length()+toCompress.length();     
    }
    //After reaching 140 characters, concatenate the rest of toCompress to compressed
    compressed.concat(toCompress);

    System.out.println("Compressed phrase: ");
    System.out.println(compressed);
    System.out.print(compressed.length()); 
    scan.close();
}