
import java.util.Scanner;

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

		//コンソールに入力した値を取得
		String a = sc.next();

		if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("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);

		//コンソールに入力した値を取得
		String a = sc.next();

		if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("a");
		}
		sc.close();
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		//コンソールに入力した値を取得
		String a = sc.next();

		if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("a");
		}
		sc.close();
	} main {
		Scanner sc = new Scanner(System.in);

		//コンソールに入力した値を取得
		String a = sc.next();

		if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("a");
		}
		sc.close();
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String a = sc.next(); a sc.next() sc.next sc if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("a");
		} a.matches("[A-Z]+") a.matches a "[A-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" sc.close() sc.close sc String[] args args public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		//コンソールに入力した値を取得
		String a = sc.next();

		if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("a");
		}
		sc.close();
	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		//コンソールに入力した値を取得
		String a = sc.next();

		if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("a");
		}
		sc.close();
	}
} Main

import java.util.Scanner;

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

		//コンソールに入力した値を取得
		String a = sc.next();

		if(a.matches("[A-Z]+")) {
			System.out.println("A");
		}else {
			System.out.println("a");
		}
		sc.close();
	}
}
