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<stdlib.h>
int isPalindrome(char str[],int l,int h) 
{ 
    // Start from leftmost and rightmost 
    // Keep comparing characters while they are same 
    while (h > l) 
    { 
        if (str[l++] != str[h--]) 
        { 
            return 0; 
        } 
    } 
    return 1;
    // printf("%s is palindrome", str); 
} 
int main()
{
    int l;
    char *s = (char *)malloc(sizeof(char)*100);
    scanf("%s",s);
    l = strlen(s);
    if(isPalindrome(s,0,l-1)==1 && isPalindrome(s,0,((l-1)/2)-1)==1 && isPalindrome(s,((l+3)/2)-1,l-1)==1)
    {
        printf("Yes");
    }
    else
    {
        printf("No\n");
    }
    return 0;
}