import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int L = s.length();
        String A = s.substring(0, L/2);
        String A2 = s.substring(((L+3)/2)-1, L);
        if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int L = s.length();
        String A = s.substring(0, L/2);
        String A2 = s.substring(((L+3)/2)-1, L);
        if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    }
} Main public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int L = s.length();
        String A = s.substring(0, L/2);
        String A2 = s.substring(((L+3)/2)-1, L);
        if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    } main {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int L = s.length();
        String A = s.substring(0, L/2);
        String A2 = s.substring(((L+3)/2)-1, L);
        if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc int L = s.length(); L s.length() s.length s String A = s.substring(0, L/2); A s.substring(0, L/2) s.substring s 0 L/2 L 2 String A2 = s.substring(((L+3)/2)-1, L); A2 s.substring(((L+3)/2)-1, L) s.substring s ((L+3)/2)-1 ((L+3)/2) (L+3) L 3 2 1 L if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        } A.equals(A2) A.equals A A2 {
            System.out.println("Yes");
        } System.out.println("Yes") System.out.println System.out System System.out "Yes" {
            System.out.println("No");
        } 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) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int L = s.length();
        String A = s.substring(0, L/2);
        String A2 = s.substring(((L+3)/2)-1, L);
        if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    }
} public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int L = s.length();
        String A = s.substring(0, L/2);
        String A2 = s.substring(((L+3)/2)-1, L);
        if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int L = s.length();
        String A = s.substring(0, L/2);
        String A2 = s.substring(((L+3)/2)-1, L);
        if(A.equals(A2)){
            System.out.println("Yes");
        }else{
            System.out.println("No");
        }
    }
}
