import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String s = scanner.nextLine().toLowerCase();
        int a = s.length();
        boolean flag = false;

            for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            }

        if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        }
    }
} import java.util.ArrayList; ArrayList java.util import java.util.Arrays; Arrays java.util import java.util.HashMap; HashMap java.util import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String s = scanner.nextLine().toLowerCase();
        int a = s.length();
        boolean flag = false;

            for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            }

        if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        }
    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String s = scanner.nextLine().toLowerCase();
        int a = s.length();
        boolean flag = false;

            for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            }

        if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        }
    } main {
        Scanner scanner = new Scanner(System.in);

        String s = scanner.nextLine().toLowerCase();
        int a = s.length();
        boolean flag = false;

            for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            }

        if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        }
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) String s = scanner.nextLine().toLowerCase(); s scanner.nextLine().toLowerCase() scanner.nextLine().toLowerCase scanner.nextLine() scanner.nextLine scanner int a = s.length(); a s.length() s.length s boolean flag = false; flag false for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            } int i = 3; int i = 3; i 3 i < a i a i+=2 i+=2 i 2 {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            } {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            } if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                } s.charAt(i)==s.charAt(i-1) s.charAt(i) s.charAt s i s.charAt(i-1) s.charAt s i-1 i 1 {
                    flag = true;
                } flag = true flag true {
                    flag = false;
                    break;
                } flag = false flag false break; if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        } flag==false flag false {
            System.out.println("No");
        } System.out.println("No") System.out.println System.out System System.out "No" {
            System.out.println("Yes");
        } System.out.println("Yes") System.out.println System.out System System.out "Yes" String[] args args public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String s = scanner.nextLine().toLowerCase();
        int a = s.length();
        boolean flag = false;

            for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            }

        if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        }
    }
} public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String s = scanner.nextLine().toLowerCase();
        int a = s.length();
        boolean flag = false;

            for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            }

        if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        }
    }
} Main
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String s = scanner.nextLine().toLowerCase();
        int a = s.length();
        boolean flag = false;

            for (int i = 3; i < a; i+=2) {
                if (s.charAt(i)==s.charAt(i-1)) {
                    flag = true;
                }else {
                    flag = false;
                    break;
                }
            }

        if (flag==false){
            System.out.println("No");
        }else {
            System.out.println("Yes");
        }
    }
}
