import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        String t = sc.nextLine();
        sc.close();

        if(s.equals(t.substring(0,t.length()-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 s = sc.nextLine();
        String t = sc.nextLine();
        sc.close();

        if(s.equals(t.substring(0,t.length()-1))) {
            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 t = sc.nextLine();
        sc.close();

        if(s.equals(t.substring(0,t.length()-1))) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    } main {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        String t = sc.nextLine();
        sc.close();

        if(s.equals(t.substring(0,t.length()-1))) {
            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 t = sc.nextLine(); t sc.nextLine() sc.nextLine sc sc.close() sc.close sc if(s.equals(t.substring(0,t.length()-1))) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        } s.equals(t.substring(0,t.length()-1)) s.equals s t.substring(0,t.length()-1) t.substring t 0 t.length()-1 t.length() t.length t 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 s = sc.nextLine();
        String t = sc.nextLine();
        sc.close();

        if(s.equals(t.substring(0,t.length()-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 s = sc.nextLine();
        String t = sc.nextLine();
        sc.close();

        if(s.equals(t.substring(0,t.length()-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 s = sc.nextLine();
        String t = sc.nextLine();
        sc.close();

        if(s.equals(t.substring(0,t.length()-1))) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
}
