Write your code in the file StringRec.java. For this problem, the following rest

Question

Write your code in the file StringRec.java. For this problem, the following restrictions apply:

YOUR CODE MUST BE RECURSIVE.

Do not use loops (while, do/while, or for).

Do not declare any variables outside of a method. You may declare local variables inside a method.

Complete the following method:

public static String decompress(String compressedText): Decompress the input text, which has been compressed using the RLE algorithm (previous hw assignment):

Run-length encoding (RLE) is a simple "compression algorithm" (an algorithm which takes a block of data and reduces its size, producing a block that contains the same information in less space). It works by replacing repetitive sequences of identical data items with short "tokens" that represent entire sequences. Applying RLE to a string involves finding sequences in the string where the same character repeats. Each such sequence should be replaced by a "token" consisting of:

the number of characters in the sequence

the repeating character

If a character does not repeat, it should be left alone.

For example, consider the following string:

After applying the RLE algorithm, this string is converted into:

In the compressed string, "9w" represents a sequence of 9 consecutive lowercase "w" characters. "5e" represents 5 consecutive lowercase "e" characters, etc.

You may assume that the character counts will be single-digit numbers (a character will not repeat more than 9 times consecutively).

Hint #1: remember that characters are represented by numeric codes. You can decrement a character variable as follows:

Hint #2: You probably will not need to use this hint for this problem. However, a fast way to convert a digit character into the numeric value of the digit is to subtract the character code for the digit zero:

Explanation / Answer

so we have use recursive methods for the compress the string variable and prints out as required

program

public class StringRec {

    public static String decompress(String compressedText) {
        StringBuffer d = new StringBuffer();
           int i=0;
           if( i < compressedText.length())
           {
            int runLength = 1;
           int j=i+1;
              if(j < compressedText.length() && compressedText.charAt(i) == compressedText.charAt(i+1)){
               runLength++;
                i++;
            }
            d.append(runLength);
            d.append(compressedText.charAt(i));
           i++;
        }
        return d.toString();
    }



    public static void main(String[] args) {
        String example = "SS";
        System.out.println(decompress(example));
           }
}

output

D:>javac StringRec.java

D:>java StringRec
2S

D:>

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