import java.util.Scanner;


public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		char c = sc.next().charAt(0);
		System.out.println(Character.isUpperCase(c) ? "A" : "a");
		sc.close();
	}

} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		char c = sc.next().charAt(0);
		System.out.println(Character.isUpperCase(c) ? "A" : "a");
		sc.close();
	}

} Main public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		char c = sc.next().charAt(0);
		System.out.println(Character.isUpperCase(c) ? "A" : "a");
		sc.close();
	} main {

		Scanner sc = new Scanner(System.in);
		char c = sc.next().charAt(0);
		System.out.println(Character.isUpperCase(c) ? "A" : "a");
		sc.close();
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) char c = sc.next().charAt(0); c sc.next().charAt(0) sc.next().charAt sc.next() sc.next sc 0 System.out.println(Character.isUpperCase(c) ? "A" : "a") System.out.println System.out System System.out Character.isUpperCase(c) ? "A" : "a" Character.isUpperCase(c) Character.isUpperCase Character c "A" "a" sc.close() sc.close sc String[] args args public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		char c = sc.next().charAt(0);
		System.out.println(Character.isUpperCase(c) ? "A" : "a");
		sc.close();
	}

} public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		char c = sc.next().charAt(0);
		System.out.println(Character.isUpperCase(c) ? "A" : "a");
		sc.close();
	}

} Main
import java.util.Scanner;


public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		char c = sc.next().charAt(0);
		System.out.println(Character.isUpperCase(c) ? "A" : "a");
		sc.close();
	}

}