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 (1.42.0) (judge verdict: Accepted)

// https://atcoder.jp/contests/abc159/tasks/abc159_b

use proconio::input;

fn main() {
    input! { s: String, }
    println!("{}", if is_strong(&s) { "Yes" } else { "No" });
}

fn is_strong(s: &String) -> bool {
    let len = s.len();
    let a = &s[..len / 2];
    let b = &s[(len + 2) / 2..];
    let rev_a = a.chars().rev().collect::<String>();
    a.to_string() == rev_a && b.to_string() == rev_a
}