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 JavaScript (node.js v5.12) (judge verdict: Accepted)

const Main = function(input){
function r(input){
var str = new String(input);
var out = "";
 for(var i = str.length; i > 0 ; i--){
   out += str.charAt(i - 1);
 }
return out;
};
S = new String(input.split("\n")[0]);
var n = S.length;
if(r(S) == S){
  var b = S.substring(-1,(n-1)/2);
  if(r(b) == b){
    var c = S.substring((n+3)/2-1,n);
    if(r(c) == c){
      console.log("Yes");
    }else{console.log("No");}
  }else{console.log("No");}
}else{console.log("No");}
};
Main(require("fs").readFileSync("/dev/stdin", "utf8"));