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 C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
 
int main()
{
	char tako[101];
  	int b;
  int c;
  int d;
  int e;
  int f;
  int g;
  int h;
	
   b = 0;
	scanf("%s", tako);

  while (tako[c] != 0)
  {
    c++;
  }
  d = c;
  e = c - 1;
  g = c/2;
	while(g > 0)
    {
      if (tako[b] != tako[e])
      {
        printf("No");
        return 0;
      }
      b++;
      g--;
      e--;
    }
  d = (d - 1)/2;
  f = d - 1;
  b = 0;
  h = d/2;
  while (h > 0)
  {
    if (tako[b] != tako[f])
    {
      printf("No");
      return 0;
    }
    b++;
    h--;
    f--;
  }
  printf("Yes");
    return 0;
}