import java.util.*;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        char ch = sc.next().charAt(0);

        if (Character.isUpperCase(ch))
            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);
        char ch = sc.next().charAt(0);

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

        if (Character.isUpperCase(ch))
            System.out.println('A');
        else
            System.out.println('a');
    } main {
        Scanner sc = new Scanner(System.in);
        char ch = sc.next().charAt(0);

        if (Character.isUpperCase(ch))
            System.out.println('A');
        else
            System.out.println('a');
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) char ch = sc.next().charAt(0); ch sc.next().charAt(0) sc.next().charAt sc.next() sc.next sc 0 if (Character.isUpperCase(ch))
            System.out.println('A');
        else
            System.out.println('a'); Character.isUpperCase(ch) Character.isUpperCase Character ch System.out.println('A') System.out.println System.out System System.out '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);
        char ch = sc.next().charAt(0);

        if (Character.isUpperCase(ch))
            System.out.println('A');
        else
            System.out.println('a');
    }
}
