import java.util.Scanner;
public class Main {
    public static void main(String[] args){
    
    Scanner sc = new Scanner(System.in);
    String S  = sc.next();
    char[]ss = S.toCharArray();
 
    if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	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 sc = new Scanner(System.in);
    String S  = sc.next();
    char[]ss = S.toCharArray();
 
    if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	System.out.println("A");
    }else{
	System.out.println("a");
      }
}
} Main public static void main(String[] args){
    
    Scanner sc = new Scanner(System.in);
    String S  = sc.next();
    char[]ss = S.toCharArray();
 
    if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	System.out.println("A");
    }else{
	System.out.println("a");
      }
} main {
    
    Scanner sc = new Scanner(System.in);
    String S  = sc.next();
    char[]ss = S.toCharArray();
 
    if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	System.out.println("A");
    }else{
	System.out.println("a");
      }
} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String S  = sc.next(); S sc.next() sc.next sc char[]ss = S.toCharArray(); ss S.toCharArray() S.toCharArray S if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	System.out.println("A");
    }else{
	System.out.println("a");
      } ss[0]+0 >= 65 && ss[0]+0<= 90 ss[0]+0 >= 65 ss[0]+0 ss[0] ss 0 0 65 ss[0]+0<= 90 ss[0]+0 ss[0] ss 0 0 90 {
    	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 sc = new Scanner(System.in);
    String S  = sc.next();
    char[]ss = S.toCharArray();
 
    if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	System.out.println("A");
    }else{
	System.out.println("a");
      }
}
} public class Main {
    public static void main(String[] args){
    
    Scanner sc = new Scanner(System.in);
    String S  = sc.next();
    char[]ss = S.toCharArray();
 
    if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	System.out.println("A");
    }else{
	System.out.println("a");
      }
}
} Main
import java.util.Scanner;
public class Main {
    public static void main(String[] args){
    
    Scanner sc = new Scanner(System.in);
    String S  = sc.next();
    char[]ss = S.toCharArray();
 
    if(ss[0]+0 >= 65 && ss[0]+0<= 90){
    	System.out.println("A");
    }else{
	System.out.println("a");
      }
}
}