Problem:
Score : 200 points

Problem Statement

A string S of an odd length is said to be a strong palindrome if and only if all of the following conditions are satisfied:

S is a palindrome.

Let N be the length of S. The string formed by the 1-st through ((N-1)/2)-th characters of S is a palindrome.

The string consisting of the (N+3)/2-st through N-th characters of S is a palindrome.

Determine whether S is a strong palindrome.

Constraints

S consists of lowercase English letters.

The length of S is an odd number between 3 and 99 (inclusive).

Input

Input is given from Standard Input in the following format:

S

Output

If S is a strong palindrome, print Yes;
otherwise, print No.

Sample Input 1

akasaka

Sample Output 1

Yes

S is akasaka.

The string formed by the 1-st through the 3-rd characters is aka.

The string formed by the 5-th through the 7-th characters is aka.
All of these are palindromes, so S is a strong palindrome.

Sample Input 2

level

Sample Output 2

No

Sample Input 3

atcoder

Sample Output 3

No

Solution in Scala (2.11.7) (judge verdict: Accepted)

object Main extends App {
	val S = scala.io.StdIn.readLine.toList.toArray
	val lngth = S.size

	val T1 = S.take((lngth - 1)/2)
	val T2 = S.drop((lngth + 1)/2)

	val flg1 = S.zip(S.reverse).map{case (a, b) => a==b}.map{case true => 0; case false => 1}.sum == 0
	val flg2 = T1.zip(T1.reverse).map{case (a, b) => a==b}.map{case true => 0; case false => 1}.sum == 0
	val flg3 = T2.zip(T2.reverse).map{case (a, b) => a==b}.map{case true => 0; case false => 1}.sum == 0

	if( flg1 && flg2 && flg3 ) println("Yes")
	else println("No")
}