import java.util.Scanner;
 
public class Main {
 
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		
		char a = scan.next().charAt(0);
		
		if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		}
		
		scan.close();
	}
} import java.util.Scanner; Scanner java.util public class Main {
 
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		
		char a = scan.next().charAt(0);
		
		if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		}
		
		scan.close();
	}
} Main public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		
		char a = scan.next().charAt(0);
		
		if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		}
		
		scan.close();
	} main {
		Scanner scan = new Scanner(System.in);
		
		char a = scan.next().charAt(0);
		
		if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		}
		
		scan.close();
	} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) char a = scan.next().charAt(0); a scan.next().charAt(0) scan.next().charAt scan.next() scan.next scan 0 if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		} Character.isUpperCase(a) Character.isUpperCase Character a {
			System.out.println("A");	// 大文字
		} System.out.println("A") System.out.println System.out System System.out "A" {
			System.out.println("a");	// 小文字
		} System.out.println("a") System.out.println System.out System System.out "a" scan.close() scan.close scan String[] args args public class Main {
 
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		
		char a = scan.next().charAt(0);
		
		if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		}
		
		scan.close();
	}
} public class Main {
 
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		
		char a = scan.next().charAt(0);
		
		if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		}
		
		scan.close();
	}
} Main
import java.util.Scanner;
 
public class Main {
 
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		
		char a = scan.next().charAt(0);
		
		if (Character.isUpperCase(a)) {
			System.out.println("A");	// 大文字
		}
		else {
			System.out.println("a");	// 小文字
		}
		
		scan.close();
	}
}