import java.io.IOException;
import java.util.Scanner;

public class Main{
	public static void main(String[] args){
    	Scanner scanner = new Scanner(System.in);
      	String s = scanner.next();
 	    char c = s.charAt(0);
        System.out.println(Character.isUpperCase(c) ? 'A' : 'a');
    }
} import java.io.IOException; IOException java.io import java.util.Scanner; Scanner java.util public class Main{
	public static void main(String[] args){
    	Scanner scanner = new Scanner(System.in);
      	String s = scanner.next();
 	    char c = s.charAt(0);
        System.out.println(Character.isUpperCase(c) ? 'A' : 'a');
    }
} Main public static void main(String[] args){
    	Scanner scanner = new Scanner(System.in);
      	String s = scanner.next();
 	    char c = s.charAt(0);
        System.out.println(Character.isUpperCase(c) ? 'A' : 'a');
    } main {
    	Scanner scanner = new Scanner(System.in);
      	String s = scanner.next();
 	    char c = s.charAt(0);
        System.out.println(Character.isUpperCase(c) ? 'A' : 'a');
    } Scanner scanner = new Scanner(System.in); scanner new Scanner(System.in) String s = scanner.next(); s scanner.next() scanner.next scanner char c = s.charAt(0); c s.charAt(0) s.charAt s 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' String[] args args public class Main{
	public static void main(String[] args){
    	Scanner scanner = new Scanner(System.in);
      	String s = scanner.next();
 	    char c = s.charAt(0);
        System.out.println(Character.isUpperCase(c) ? 'A' : 'a');
    }
} public class Main{
	public static void main(String[] args){
    	Scanner scanner = new Scanner(System.in);
      	String s = scanner.next();
 	    char c = s.charAt(0);
        System.out.println(Character.isUpperCase(c) ? 'A' : 'a');
    }
} Main
import java.io.IOException;
import java.util.Scanner;

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