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