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>
#include<string.h>
#include<math.h>
int main()
{
	char n[1000];
	char a1[200];
	char b1[200];
	scanf("%s",&n);
	int s,a,b,i;
	s=strlen(n);
	a=(s-1)/2;
	b=(s+3)/2; 
	for(i=0;i<a;i++)
	a1[i]=n[i];
	for(i=b-1;i<s;i++)
	b1[i-b+1]=n[i];
	int p=1;
	for(i=0;i<a;i++)
	if(a1[i]!=a1[a-i-1])
	p=0;
	for(i=0;i<a;i++)
	{
		if(a1[i]!=b1[i])
		p=0;
	}
	if(p==1)
	printf("Yes");
	else
	printf("No");
}