String problems

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

public class Main
{
	public static void main (String[] args) throws java.lang.Exception                          // input  heey
	{                                                                                           //output  heeeey
		Scanner sc = new Scanner(System.in);
       String s = sc.next();
     // System.out.print(s.replace("e","ee"));
      //int count = s.length() -2;
      int count=0;
      for(int i=0;i<s.length();i++){
        if(s.charAt(i)=='e'){
          count++;
        }
        }
        String arr ="h";
        for(int i=0;i<2*count;i++){
          arr += "e";
        }
        arr += "y";
        System.out.println(arr);
      
	}
}



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

public class Main
{
	public static void main (String[] args) throws java.lang.Exception                        
	{
		Scanner sc = new Scanner(System.in);                                      // input     Kimo-Manas-Petter
      String s1 = sc.next();                                                  //output     KMP
      String ret ="";
       ret += s1.charAt(0);
      for(int i=0;i<s1.length();i++){
        if(s1.charAt(i)=='-'){
          ret += s1.charAt(i+1);
        }
      }
      System.out.println(ret);
      
	}
}


Shuffle String
Given a string s and an integer array indices of the same length.
The string s will be shuffled such that the character at the ith position moves to indices[i] in the shuffled string.
Print the shuffled string.

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

public class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
	Scanner sc = new Scanner(System.in);                                // input  8
      int n = sc.nextInt();                                           // leetcode
     String s1 =sc.next();                                            // 4 5 6 7 0 2 1 3
      int num[] = new int[n];                                         // codeleet
      for(int i=0;i<n;i++){
        num[i] = sc.nextInt();
      }
      char arr[]=new char[n];
      for(int i=0;i<s1.length();i++){
        char ch = s1.charAt(i);
        int target = num[i];
        arr[target] = ch;
      }
      System.out.println(arr);
	}
}
     //CHECK WHEATHER A STRING IS PALINDROME OR NOT
     import java.util.*;
public class Main
{
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
	   int start =0;
		int end = s.length()-1;
		 while(start<end){
		     if(s.charAt(start)!=s.charAt(end)){
		         System.out.println("string is not palindrome");
		         return;
		     }
		     start++;
		     end--;
		 }
		 System.out.println("string is  palindrome");
	}
}

          /*         Last index of One
                Given a string S consisting only 0s and 1s, find the last index of the 1 present in it.                           */

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

public class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
	     Scanner sc = new Scanner(System.in);
         String s = sc.next();
      
      int index = -1;
     for (int i = 0;i<s.length();i++)
     {
        if(s.charAt(i) =='1')
          {
            index = i;
          }
    }
        System.out.print(index);
	}
}