import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc= new Scanner(System.in);
        int alpha = sc.next().charAt(0);
        if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a");
        if ((int) 'A' <= alpha && alpha <= (int) 'Z') 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);
        int alpha = sc.next().charAt(0);
        if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a");
        if ((int) 'A' <= alpha && alpha <= (int) 'Z') System.out.println("A");
    } 
} Main public static void main(String[] args) {
        Scanner sc= new Scanner(System.in);
        int alpha = sc.next().charAt(0);
        if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a");
        if ((int) 'A' <= alpha && alpha <= (int) 'Z') System.out.println("A");
    } main {
        Scanner sc= new Scanner(System.in);
        int alpha = sc.next().charAt(0);
        if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a");
        if ((int) 'A' <= alpha && alpha <= (int) 'Z') System.out.println("A");
    } Scanner sc= new Scanner(System.in); sc new Scanner(System.in) int alpha = sc.next().charAt(0); alpha sc.next().charAt(0) sc.next().charAt sc.next() sc.next sc 0 if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a"); (int) 'a' <= alpha && alpha <= (int) 'z' (int) 'a' <= alpha (int) 'a' alpha alpha <= (int) 'z' alpha (int) 'z' System.out.println("a") System.out.println System.out System System.out "a" if ((int) 'A' <= alpha && alpha <= (int) 'Z') System.out.println("A"); (int) 'A' <= alpha && alpha <= (int) 'Z' (int) 'A' <= alpha (int) 'A' alpha alpha <= (int) 'Z' alpha (int) 'Z' 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);
        int alpha = sc.next().charAt(0);
        if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a");
        if ((int) 'A' <= alpha && alpha <= (int) 'Z') System.out.println("A");
    } 
} public class Main {
    public static void main(String[] args) {
        Scanner sc= new Scanner(System.in);
        int alpha = sc.next().charAt(0);
        if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a");
        if ((int) 'A' <= alpha && alpha <= (int) 'Z') System.out.println("A");
    } 
} Main
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc= new Scanner(System.in);
        int alpha = sc.next().charAt(0);
        if ((int) 'a' <= alpha && alpha <= (int) 'z') System.out.println("a");
        if ((int) 'A' <= alpha && alpha <= (int) 'Z') System.out.println("A");
    } 
}