import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String S = sc.nextLine();
        String[] sp = S.split("");
        int N = sp.length;
        
        String first = "";
        String last = "";
        
        for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        }
        for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        }
        

        if(first.equals(last)) {
            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 S = sc.nextLine();
        String[] sp = S.split("");
        int N = sp.length;
        
        String first = "";
        String last = "";
        
        for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        }
        for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        }
        

        if(first.equals(last)) {
            System.out.println("Yes");
        }else {
            System.out.println("No");
        }
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String S = sc.nextLine();
        String[] sp = S.split("");
        int N = sp.length;
        
        String first = "";
        String last = "";
        
        for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        }
        for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        }
        

        if(first.equals(last)) {
            System.out.println("Yes");
        }else {
            System.out.println("No");
        }
    } main {
        Scanner sc = new Scanner(System.in);
        String S = sc.nextLine();
        String[] sp = S.split("");
        int N = sp.length;
        
        String first = "";
        String last = "";
        
        for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        }
        for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        }
        

        if(first.equals(last)) {
            System.out.println("Yes");
        }else {
            System.out.println("No");
        }
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String S = sc.nextLine(); S sc.nextLine() sc.nextLine sc String[] sp = S.split(""); sp S.split("") S.split S "" int N = sp.length; N sp.length sp sp.length String first = ""; first "" String last = ""; last "" for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        } int i = 0; int i = 0; i 0 i < (N-1)/2 i (N-1)/2 (N-1) N 1 2 i++ i++ i {
            first += sp[i];
        } {
            first += sp[i];
        } first += sp[i] first sp[i] sp i for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        } int i = ((N+3)/2)-1; int i = ((N+3)/2)-1; i ((N+3)/2)-1 ((N+3)/2) (N+3) N 3 2 1 i < N i N i++ i++ i {
            last += sp[i];
        } {
            last += sp[i];
        } last += sp[i] last sp[i] sp i if(first.equals(last)) {
            System.out.println("Yes");
        }else {
            System.out.println("No");
        } first.equals(last) first.equals first last {
            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 S = sc.nextLine();
        String[] sp = S.split("");
        int N = sp.length;
        
        String first = "";
        String last = "";
        
        for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        }
        for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        }
        

        if(first.equals(last)) {
            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 S = sc.nextLine();
        String[] sp = S.split("");
        int N = sp.length;
        
        String first = "";
        String last = "";
        
        for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        }
        for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        }
        

        if(first.equals(last)) {
            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 S = sc.nextLine();
        String[] sp = S.split("");
        int N = sp.length;
        
        String first = "";
        String last = "";
        
        for(int i = 0; i < (N-1)/2; i++) {
            first += sp[i];
        }
        for(int i = ((N+3)/2)-1; i < N; i++) {
            last += sp[i];
        }
        

        if(first.equals(last)) {
            System.out.println("Yes");
        }else {
            System.out.println("No");
        }
    }
}