import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		String t = sc.next();

		System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "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.next();
		String t = sc.next();

		System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "No");
	}
} Main public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		String t = sc.next();

		System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "No");
	} main {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		String t = sc.next();

		System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "No");
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc String t = sc.next(); t sc.next() sc.next sc System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "No") System.out.println System.out System System.out t.matches(s + "[a-z]{1}") ? "Yes" : "No" t.matches(s + "[a-z]{1}") t.matches t s + "[a-z]{1}" s "[a-z]{1}" "Yes" "No" String[] args args public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		String t = sc.next();

		System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "No");
	}
} public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		String t = sc.next();

		System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "No");
	}
} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.next();
		String t = sc.next();

		System.out.println(t.matches(s + "[a-z]{1}") ? "Yes" : "No");
	}
}