import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        String T = sc.next();
        
        int lgt = S.length();
        if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        String T = sc.next();
        
        int lgt = S.length();
        if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} Main public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        String T = sc.next();
        
        int lgt = S.length();
        if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    } main {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        String T = sc.next();
        
        int lgt = S.length();
        if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("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 int lgt = S.length(); lgt S.length() S.length S if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("No");
        } T.substring(0,lgt).equals(S) T.substring(0,lgt).equals T.substring(0,lgt) T.substring T 0 lgt S {
            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) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        String T = sc.next();
        
        int lgt = S.length();
        if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        String T = sc.next();
        
        int lgt = S.length();
        if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
} Main
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String S = sc.next();
        String T = sc.next();
        
        int lgt = S.length();
        if(T.substring(0,lgt).equals(S)){
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
}
