import java.util.Scanner;



public class Main {

    public static void main(String[] args) {
        Scanner s=new Scanner(System.in);
        
        String in=s.next();
        
        if(in.charAt(0)<92) {
        	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 s=new Scanner(System.in);
        
        String in=s.next();
        
        if(in.charAt(0)<92) {
        	System.out.println("A");
        }else {
        	System.out.println("a");
        }
       
    }
} Main public static void main(String[] args) {
        Scanner s=new Scanner(System.in);
        
        String in=s.next();
        
        if(in.charAt(0)<92) {
        	System.out.println("A");
        }else {
        	System.out.println("a");
        }
       
    } main {
        Scanner s=new Scanner(System.in);
        
        String in=s.next();
        
        if(in.charAt(0)<92) {
        	System.out.println("A");
        }else {
        	System.out.println("a");
        }
       
    } Scanner s=new Scanner(System.in); s new Scanner(System.in) String in=s.next(); in s.next() s.next s if(in.charAt(0)<92) {
        	System.out.println("A");
        }else {
        	System.out.println("a");
        } in.charAt(0)<92 in.charAt(0) in.charAt in 0 92 {
        	System.out.println("A");
        } System.out.println("A") System.out.println System.out System System.out "A" {
        	System.out.println("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 s=new Scanner(System.in);
        
        String in=s.next();
        
        if(in.charAt(0)<92) {
        	System.out.println("A");
        }else {
        	System.out.println("a");
        }
       
    }
} public class Main {

    public static void main(String[] args) {
        Scanner s=new Scanner(System.in);
        
        String in=s.next();
        
        if(in.charAt(0)<92) {
        	System.out.println("A");
        }else {
        	System.out.println("a");
        }
       
    }
} Main
import java.util.Scanner;



public class Main {

    public static void main(String[] args) {
        Scanner s=new Scanner(System.in);
        
        String in=s.next();
        
        if(in.charAt(0)<92) {
        	System.out.println("A");
        }else {
        	System.out.println("a");
        }
       
    }
}