import java.util.Scanner;

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