import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        char s = a.charAt(0);
        if(Character.isUpperCase(s)) {
            System.out.println("A");
        }else {
            System.out.println("a");
        }
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        char s = a.charAt(0);
        if(Character.isUpperCase(s)) {
            System.out.println("A");
        }else {
            System.out.println("a");
        }
    }
} Main public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        char s = a.charAt(0);
        if(Character.isUpperCase(s)) {
            System.out.println("A");
        }else {
            System.out.println("a");
        }
    } main {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        char s = a.charAt(0);
        if(Character.isUpperCase(s)) {
            System.out.println("A");
        }else {
            System.out.println("a");
        }
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String a = sc.next(); a sc.next() sc.next sc char s = a.charAt(0); s a.charAt(0) a.charAt a 0 if(Character.isUpperCase(s)) {
            System.out.println("A");
        }else {
            System.out.println("a");
        } Character.isUpperCase(s) Character.isUpperCase Character s {
            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) throws Exception {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        char s = a.charAt(0);
        if(Character.isUpperCase(s)) {
            System.out.println("A");
        }else {
            System.out.println("a");
        }
    }
} public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        char s = a.charAt(0);
        if(Character.isUpperCase(s)) {
            System.out.println("A");
        }else {
            System.out.println("a");
        }
    }
} Main
import java.util.*;

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