import java.util.Scanner;
public class Main {

	public static void main(String[] args) {
		Scanner input=new Scanner(System.in);// TODO Auto-generated method stub
		String alfa=input.next();
		if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		}
	}

} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner input=new Scanner(System.in);// TODO Auto-generated method stub
		String alfa=input.next();
		if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		}
	}

} Main public static void main(String[] args) {
		Scanner input=new Scanner(System.in);// TODO Auto-generated method stub
		String alfa=input.next();
		if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		}
	} main {
		Scanner input=new Scanner(System.in);// TODO Auto-generated method stub
		String alfa=input.next();
		if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		}
	} Scanner input=new Scanner(System.in); input new Scanner(System.in) String alfa=input.next(); alfa input.next() input.next input if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		} alfa.equals(alfa.toLowerCase()) alfa.equals alfa alfa.toLowerCase() alfa.toLowerCase alfa {
			System.out.println("a");
		} System.out.println("a") System.out.println System.out System System.out "a" {
			System.out.println("A");
		} System.out.println("A") System.out.println System.out System System.out "A" String[] args args public class Main {

	public static void main(String[] args) {
		Scanner input=new Scanner(System.in);// TODO Auto-generated method stub
		String alfa=input.next();
		if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		}
	}

} public class Main {

	public static void main(String[] args) {
		Scanner input=new Scanner(System.in);// TODO Auto-generated method stub
		String alfa=input.next();
		if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		}
	}

} Main
import java.util.Scanner;
public class Main {

	public static void main(String[] args) {
		Scanner input=new Scanner(System.in);// TODO Auto-generated method stub
		String alfa=input.next();
		if(alfa.equals(alfa.toLowerCase())) {
			System.out.println("a");
		}
		else {
			System.out.println("A");
		}
	}

}