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 Ruby (2.3.3) (judge verdict: Accepted)

def circularSentence?(string)
  firstSentence = string[0...string.size/2]
  secondSentence = string[string.size/2...string.size].reverse
  if string.size.odd?
    secondSentence = string[string.size/2+1...string.size].reverse
  end
  return firstSentence  == secondSentence ? true : false
end
s=gets.chomp
n=s.size 
puts s == s.reverse && circularSentence?(s[0...(n-1)/2]) && circularSentence?(s[(n+3)/2-1...n]) ? :Yes : :No