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 9.2.1) (judge verdict: Accepted)

#include<stdio.h>
#include<string.h>

int main()
{
    int len,i,j,d;
    char s1[99];
    scanf("%s",&s1);
    len = strlen(s1);
    char s2[len+1];
    for(i=0,j=len-1;j>=0;i++,j--)
    {
        s2[i] = s1[j];
    }
    s2[i]='\0';

    d=strcmp(s1,s2);
    if(d==0)
    {
        char s3[(len/2)+1],s[(len/2)+1];
        for(i=0,j=0;j<=(len/2)-1;i++,j++)
        {
           s3[i] = s1[j];
        }
        s3[i]='\0';

        for(i=0,j=(len/2)-1;j>=0;i++,j--)
        {
            s[i]=s3[j];
        }
        s[i]='\0';

        int e = strcmp(s,s3);

        if(e==0)
        {
            for(i=0,j=(len/2)+1;j<=len-1;i++,j++)
            {
                s3[i]=s1[j];
            }
            s3[i]='\0';

            for(i=0,j=(len/2)-1;j>=0;i++,j--)
            {
            s[i]=s3[j];
            }
            s[i]='\0';

            e = strcmp(s,s3);

            if(e==0)
            {
                printf("Yes");

            }
            else
                printf("No");

        }
        else{
            printf("No");
        }

    }
    else{
        printf("No");
    }
    return 0;
}