import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        char input = scanner.next().charAt(0);

        if (input >= 'a' && input <= 'z') {
            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 scanner = new Scanner(System.in);
        char input = scanner.next().charAt(0);

        if (input >= 'a' && input <= 'z') {
            System.out.println('a');
        } else {
            System.out.println('A');
        }

    }
} Main public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        char input = scanner.next().charAt(0);

        if (input >= 'a' && input <= 'z') {
            System.out.println('a');
        } else {
            System.out.println('A');
        }

    } main {
        Scanner scanner = new Scanner(System.in);
        char input = scanner.next().charAt(0);

        if (input >= 'a' && input <= 'z') {
            System.out.println('a');
        } else {
            System.out.println('A');
        }

    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) char input = scanner.next().charAt(0); input scanner.next().charAt(0) scanner.next().charAt scanner.next() scanner.next scanner 0 if (input >= 'a' && input <= 'z') {
            System.out.println('a');
        } else {
            System.out.println('A');
        } input >= 'a' && input <= 'z' input >= 'a' input 'a' input <= 'z' input 'z' {
            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 scanner = new Scanner(System.in);
        char input = scanner.next().charAt(0);

        if (input >= 'a' && input <= 'z') {
            System.out.println('a');
        } else {
            System.out.println('A');
        }

    }
} public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        char input = scanner.next().charAt(0);

        if (input >= 'a' && input <= 'z') {
            System.out.println('a');
        } else {
            System.out.println('A');
        }

    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        char input = scanner.next().charAt(0);

        if (input >= 'a' && input <= 'z') {
            System.out.println('a');
        } else {
            System.out.println('A');
        }

    }
}
