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