Java 字符串操作 : Comparing adjacent Characters in Java

Question

我有以下问题
给定一个字符串，返回一个“清理过”的字符串，其中相同的相邻字符已减少为单个字符。所以 "yyzzza" 产生 "yza"。

stringClean("yyzzza") → "yza"      
stringClean("abbbcdd") → "abcd"       
stringClean("Hello") → "Helo"

我正在尝试使用我的代码输入 stringClean("abbbcdd") → "abcd"

我的代码在下面。我在进行相邻字符比较后得到了部分附加字符串，因此从现在开始我得到了附加的 stringBuilder "sb=abc" 这不是正确的输出我应该得到输出为 "abcd",

class cleanString{

    public static String stringClean(String str){
        int startIndex = str.indexOf(str);
        char startChar = '\u0000';
        char adjacentChar = '\u0000';
        System.out.println("startIndex-->" + startIndex);
        final StringBuilder sb = new StringBuilder();

        for(startIndex = 0; startIndex < str.length(); startIndex += 1){
            startChar = str.charAt(startIndex);
            System.out.println("startIndex ::" + startIndex);
            System.out.println("startChar ::" + startChar);

            final int adjacentPosition = startIndex + 1;
            System.out.println("adjacentPosition ::" + adjacentPosition);
            if(adjacentPosition != str.length()){
                adjacentChar = str.charAt(adjacentPosition);
                System.out.println("adjacentChar ::" + adjacentChar);
            }
            if(startChar == adjacentChar){
                System.out.println("startChar ::" + startChar);
                System.out.println("adjacentChar::" + adjacentChar);

                System.out.println("Before Substring string --->" + str);
                str = str.substring(1);
                startIndex--;
                System.out.println("After Substring string --->" + str);
                System.out.println("IndexOf check ---->"
                    + sb.toString().indexOf(startChar));
                if(sb.toString().indexOf(startChar) != -1){
                    sb.append(adjacentChar);
                    System.out.println("Appended String in if part-->"
                        + sb.toString());
                }
            } else{
                str = str.substring(1);
                startIndex--;
                sb.append(startChar);
                System.out.println("Appended String --->" + sb.toString());
            }
        }// end of for loop
        return sb.toString();
    }

    //im getting output as abc...which is partial appended string      
    public static void main(String ...args){     
        String outputCleanString=new cleanString().stringClean("abbbcdd");      
        System.out.println("Cleaned String --->"+outputCleanString);
    }      

}  

*观察:*在我得到附加字符串“abc”之后，然后当我开始比较最后一组字符“dd”时，我在该部分遇到了问题。

Answer 1

如果可以接受基于正则表达式的解决方案，您可以:

str = str.replaceAll("(.)\\1+","$1");

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