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Contest: Task: Related: TaskA TaskC

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