import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        if(Character.isLowerCase(s.charAt(0))){
            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 sc = new Scanner(System.in);
        String s = sc.next();
        if(Character.isLowerCase(s.charAt(0))){
            System.out.println("a");
        }else{
            System.out.println("A");
        }
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        if(Character.isLowerCase(s.charAt(0))){
            System.out.println("a");
        }else{
            System.out.println("A");
        }
    } main {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        if(Character.isLowerCase(s.charAt(0))){
            System.out.println("a");
        }else{
            System.out.println("A");
        }
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String s = sc.next(); s sc.next() sc.next sc if(Character.isLowerCase(s.charAt(0))){
            System.out.println("a");
        }else{
            System.out.println("A");
        } Character.isLowerCase(s.charAt(0)) Character.isLowerCase Character s.charAt(0) s.charAt s 0 {
            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 sc = new Scanner(System.in);
        String s = sc.next();
        if(Character.isLowerCase(s.charAt(0))){
            System.out.println("a");
        }else{
            System.out.println("A");
        }
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        if(Character.isLowerCase(s.charAt(0))){
            System.out.println("a");
        }else{
            System.out.println("A");
        }
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        if(Character.isLowerCase(s.charAt(0))){
            System.out.println("a");
        }else{
            System.out.println("A");
        }
    }
}
