import java.util.Scanner;

public class Main {

    public static Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) {
        char c= scanner.next().charAt(0);
        if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        }
	// write your code here
    }
} import java.util.Scanner; Scanner java.util public class Main {

    public static Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) {
        char c= scanner.next().charAt(0);
        if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        }
	// write your code here
    }
} Main public static Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) public static void main(String[] args) {
        char c= scanner.next().charAt(0);
        if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        }
	// write your code here
    } main {
        char c= scanner.next().charAt(0);
        if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        }
	// write your code here
    } char c= scanner.next().charAt(0); c scanner.next().charAt(0) scanner.next().charAt scanner.next() scanner.next scanner 0 if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        } c-'A'<26 c-'A' c 'A' 26 {
            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 Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) {
        char c= scanner.next().charAt(0);
        if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        }
	// write your code here
    }
} public class Main {

    public static Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) {
        char c= scanner.next().charAt(0);
        if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        }
	// write your code here
    }
} Main
import java.util.Scanner;

public class Main {

    public static Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) {
        char c= scanner.next().charAt(0);
        if(c-'A'<26)
        {
            System.out.println("A");
        }
        else
        {
            System.out.println("a");
        }
	// write your code here
    }
}