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 Python (3.4.3) (judge verdict: Wrong Answer)

S = input()
S = list(S)
S_1 = S[0:int((len(S)-1)/2)]
S_2 = S[int((len(S)-1)/2)+1:len(S)]
if S_1 == S_2:
    if len(S_1) % 2 == 0:
        S_1_1 = S_1[0:int((len(S_1)-1)/2)+1]
        S_1_2 = S_1[int((len(S_1)-1)/2)+1:len(S_1)]
        S_2_1 = S_2[0:int((len(S_2)-1)/2)+1]
        S_2_2 = S_2[int((len(S_2)-1)/2)+1:len(S_2)]
    else:
        S_1_1 = S_1[0:int((len(S_1)-1)/2)]
        S_1_2 = S_1[int((len(S_1)-1)/2)+1:len(S_1)]
        S_2_1 = S_2[0:int((len(S_2)-1)/2)]
        S_2_2 = S_2[int((len(S_2)-1)/2)+1:len(S_2)]
    if S_1_1 == S_1_2:
        if S_2_1 == S_2_2:
            print('Yes')
        else:
            print('No')
    else:
        print('No')
else:
    print('No')