import java.util.Scanner;

public class Main {
    
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        final char a = sc.next().charAt(0);
        
        System.out.println('A' <= a && a <= 'Z' ? 'A' : 'a');
    }
} import java.util.Scanner; Scanner java.util public class Main {
    
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        final char a = sc.next().charAt(0);
        
        System.out.println('A' <= a && a <= 'Z' ? 'A' : 'a');
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        final char a = sc.next().charAt(0);
        
        System.out.println('A' <= a && a <= 'Z' ? 'A' : 'a');
    } main {
        Scanner sc = new Scanner(System.in);
        
        final char a = sc.next().charAt(0);
        
        System.out.println('A' <= a && a <= 'Z' ? 'A' : 'a');
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) final char a = sc.next().charAt(0); a sc.next().charAt(0) sc.next().charAt sc.next() sc.next sc 0 System.out.println('A' <= a && a <= 'Z' ? 'A' : 'a') System.out.println System.out System System.out 'A' <= a && a <= 'Z' ? 'A' : 'a' 'A' <= a && a <= 'Z' 'A' <= a 'A' a a <= 'Z' a 'Z' 'A' 'a' String[] args args public class Main {
    
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        final char a = sc.next().charAt(0);
        
        System.out.println('A' <= a && a <= 'Z' ? 'A' : 'a');
    }
} public class Main {
    
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        final char a = sc.next().charAt(0);
        
        System.out.println('A' <= a && a <= 'Z' ? 'A' : 'a');
    }
} Main
import java.util.Scanner;

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