Problem:
Score : 500 points

Problem Statement

You have a string A = A_1 A_2 ... A_n consisting of lowercase English letters.

You can choose any two indices i and j such that 1 \leq i \leq j \leq n and reverse substring A_i A_{i+1} ... A_j.

You can perform this operation at most once.

How many different strings can you obtain?

Constraints

1 \leq |A| \leq 200,000

A consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

A

Output

Print the number of different strings you can obtain by reversing any substring in A at most once.

Sample Input 1

aatt

Sample Output 1

5

You can obtain aatt (don't do anything), atat (reverse A[2..3]), atta (reverse A[2..4]), ttaa (reverse A[1..4]) and taat (reverse A[1..3]).

Sample Input 2

xxxxxxxxxx

Sample Output 2

1

Whatever substring you reverse, you'll always get xxxxxxxxxx.

Sample Input 3

abracadabra

Sample Output 3

44

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.Scanner;

public class Main
{
    public static boolean checkPalindrome(String s)
    {
        // reverse the given String
        String reverse = new StringBuffer(s).reverse().toString();

        // check whether the string is palindrome or not
        if (s.equals(reverse))
           return true;

        else
          return false;
    }

    public static void main (String[] args)
    {

        String s;
        Scanner sc = new Scanner(System.in);
        s = sc.nextLine();
        int len = s.length();
        int ans = 2*len;
        ans = ans -1;

        for(int i=0; i<len-1; i++){
            for(int j=i+1; j<len; j++){
                if(checkPalindrome(s.substring(i,j+1))){
                    ans -= 1;
                }
            }
        }

        System.out.println(ans);
    }


}