PairStar in Java

Given a string, compute recursively a new string where identical chars that are adjacent in the original string are separated from each other by a “*”.

pairStar(“hello”) → “hello” pairStar(“xxyy”) → “xxyy” pairStar(“aaaa”) → “aaaa”

** Input format** The first line contains the string.

Output format Print the desired output where there is a * between consecutive same characters.

Example hello Output hel*lo

Constraints 1 <= Len(str) <= 1000

Solution of PairStar:–

import java.util.*;
import java.lang.*;
import java.io.*;

public class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
		//your code here
      Scanner sc=new Scanner(System.in);
      String s=sc.next();
      System.out.print(pairstar(s));
	}
  public static String pairstar(String s)
  {
    if(s.length()<2)
      return s;
    if(s.charAt(0)==s.charAt(1))
      return s.charAt(0)+"*"+pairstar(s.substring(1));

    return s.charAt(0)+pairstar(s.substring(1));
    
  }
}