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 read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|i| i.parse().ok().unwrap())
        .collect()
}

fn is_palindrome(chars: &Vec<char>) -> bool{
    for i in 0..chars.len()/2 {
        if chars[i] != chars[chars.len()-i-1] {
            return false;
        }
    }
    return true;
}

fn main() {
    let s = read::<String>();
    let chars = s.chars().collect::<Vec<char>>();

    if !is_palindrome(&chars) {
        println!("No");
        return;
    }

    let sub_chars = s.chars().take(chars.len()/2).collect::<Vec<char>>();
    if !is_palindrome(&sub_chars) {
        println!("No");
        return;
    }
    let sub_chars = s.chars().skip((chars.len()+1)/2).collect::<Vec<char>>();
    if !is_palindrome(&sub_chars) {
        println!("No");
        return;
    }

    println!("Yes");
}