import java.util.*;

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

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