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 Rust (1.15.1) (judge verdict: Accepted)

fn main() {
    let mut line = String::new();
    std::io::stdin().read_line(&mut line).unwrap();
    let b: Vec<u8> = line.trim().as_bytes().iter().map(|a| *a).collect();
    let mut revb = b.clone();
    revb.reverse();
    let n = b.len();
    if revb == b {
        revb[0..n/2].reverse();
        if revb[0..n/2] == b[0..n/2] {
            revb[n/2+1..].reverse();
            if revb[n/2+1..] == b[n/2+1..] { // 不要そう
                println!("Yes");
                return;
            }
        }
    }
    println!("No");
}