import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		int n = s.length();

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

		sc.close();

	}
} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		int n = s.length();

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

		sc.close();

	}
} Main public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		int n = s.length();

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

		sc.close();

	} main {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		int n = s.length();

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

		sc.close();

	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc int n = s.length(); n s.length() s.length s if (s.substring(0, n / 2).equals(s.substring((n + 3) / 2-1, n))) {
			System.out.println("Yes");
		} else {
			System.out.println("No");
		} s.substring(0, n / 2).equals(s.substring((n + 3) / 2-1, n)) s.substring(0, n / 2).equals s.substring(0, n / 2) s.substring s 0 n / 2 n 2 s.substring((n + 3) / 2-1, n) s.substring s (n + 3) / 2-1 (n + 3) / 2 (n + 3) n 3 2 1 n {
			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" sc.close() sc.close sc String[] args args public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		int n = s.length();

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

		sc.close();

	}
} public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		int n = s.length();

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

		sc.close();

	}
} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		int n = s.length();

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

		sc.close();

	}
}