import java.util.*;


public class Main {
    public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		int n = str.length();
		String sub1 = str.substring(0, n/2);
		String sub2 = str.substring(((n+3)/2) -1 ,n );
		if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No");
		
    }
}
 import java.util.*; util.* java public class Main {
    public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		int n = str.length();
		String sub1 = str.substring(0, n/2);
		String sub2 = str.substring(((n+3)/2) -1 ,n );
		if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No");
		
    }
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		int n = str.length();
		String sub1 = str.substring(0, n/2);
		String sub2 = str.substring(((n+3)/2) -1 ,n );
		if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No");
		
    } main {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		int n = str.length();
		String sub1 = str.substring(0, n/2);
		String sub2 = str.substring(((n+3)/2) -1 ,n );
		if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No");
		
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String str = sc.nextLine(); str sc.nextLine() sc.nextLine sc int n = str.length(); n str.length() str.length str String sub1 = str.substring(0, n/2); sub1 str.substring(0, n/2) str.substring str 0 n/2 n 2 String sub2 = str.substring(((n+3)/2) -1 ,n ); sub2 str.substring(((n+3)/2) -1 ,n ) str.substring str ((n+3)/2) -1 ((n+3)/2) (n+3) n 3 2 1 n if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No"); sub1.equals(sub2) sub1.equals sub1 sub2 System.out.println("Yes") System.out.println System.out System System.out "Yes" System.out.println("No") System.out.println System.out System System.out "No" String[] args args public class Main {
    public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		int n = str.length();
		String sub1 = str.substring(0, n/2);
		String sub2 = str.substring(((n+3)/2) -1 ,n );
		if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No");
		
    }
} public class Main {
    public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		int n = str.length();
		String sub1 = str.substring(0, n/2);
		String sub2 = str.substring(((n+3)/2) -1 ,n );
		if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No");
		
    }
} Main
import java.util.*;


public class Main {
    public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		int n = str.length();
		String sub1 = str.substring(0, n/2);
		String sub2 = str.substring(((n+3)/2) -1 ,n );
		if (sub1.equals(sub2)) 
		    System.out.println("Yes");
		else 
		    System.out.println("No");
		
    }
}

