import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        int N = str.length();

        if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            System.out.println("Yes");
        }
        else {
            System.out.println("No");
        }
    }
} import java.util.Scanner; Scanner 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();

        if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            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();

        if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            System.out.println("Yes");
        }
        else {
            System.out.println("No");
        }
    } main {
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        int N = str.length();

        if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            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 if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            System.out.println("Yes");
        }
        else {
            System.out.println("No");
        } str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1)) str.substring(0,(N-1)/2).equals str.substring(0,(N-1)/2) str.substring str 0 (N-1)/2 (N-1) N 1 2 str.substring(((N+3)/2)-1) str.substring str ((N+3)/2)-1 ((N+3)/2) (N+3) N 3 2 1 {
            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) {
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        int N = str.length();

        if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            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();

        if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            System.out.println("Yes");
        }
        else {
            System.out.println("No");
        }
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        int N = str.length();

        if (str.substring(0,(N-1)/2).equals(str.substring(((N+3)/2)-1))) {
            System.out.println("Yes");
        }
        else {
            System.out.println("No");
        }
    }
}
