import java.util.Scanner;

public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        final String S = sc.next();
        sc.close();

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

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

        if (Character.isUpperCase(S.charAt(0))) {
            System.out.println("A");
        } else {
            System.out.println("a");
        }
        return;
    } main {
        final Scanner sc = new Scanner(System.in);
        final String S = sc.next();
        sc.close();

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

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

        if (Character.isUpperCase(S.charAt(0))) {
            System.out.println("A");
        } else {
            System.out.println("a");
        }
        return;
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        final String S = sc.next();
        sc.close();

        if (Character.isUpperCase(S.charAt(0))) {
            System.out.println("A");
        } else {
            System.out.println("a");
        }
        return;
    }
}