
import java.util.*;

public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        // 整数の入力
        // final int a = sc.nextInt();
        // 文字列の入力
        // final String s1 = sc.next();
        final String s1 = sc.next();
        sc.close();
        String result = "a";
        if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        }
        System.out.println(result);
    }
} import java.util.*; util.* java public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        // 整数の入力
        // final int a = sc.nextInt();
        // 文字列の入力
        // final String s1 = sc.next();
        final String s1 = sc.next();
        sc.close();
        String result = "a";
        if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        }
        System.out.println(result);
    }
} Main public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        // 整数の入力
        // final int a = sc.nextInt();
        // 文字列の入力
        // final String s1 = sc.next();
        final String s1 = sc.next();
        sc.close();
        String result = "a";
        if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        }
        System.out.println(result);
    } main {
        final Scanner sc = new Scanner(System.in);
        // 整数の入力
        // final int a = sc.nextInt();
        // 文字列の入力
        // final String s1 = sc.next();
        final String s1 = sc.next();
        sc.close();
        String result = "a";
        if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        }
        System.out.println(result);
    } final Scanner sc = new Scanner(System.in); sc new Scanner(System.in) final String s1 = sc.next(); s1 sc.next() sc.next sc sc.close() sc.close sc String result = "a"; result "a" if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        } Character.isUpperCase(s1.charAt(0)) Character.isUpperCase Character s1.charAt(0) s1.charAt s1 0 {
            result = "A";
        } result = "A" result "A" System.out.println(result) System.out.println System.out System System.out result final String[] args args public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        // 整数の入力
        // final int a = sc.nextInt();
        // 文字列の入力
        // final String s1 = sc.next();
        final String s1 = sc.next();
        sc.close();
        String result = "a";
        if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        }
        System.out.println(result);
    }
} public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        // 整数の入力
        // final int a = sc.nextInt();
        // 文字列の入力
        // final String s1 = sc.next();
        final String s1 = sc.next();
        sc.close();
        String result = "a";
        if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        }
        System.out.println(result);
    }
} Main

import java.util.*;

public class Main {
    public static void main(final String[] args) {
        final Scanner sc = new Scanner(System.in);
        // 整数の入力
        // final int a = sc.nextInt();
        // 文字列の入力
        // final String s1 = sc.next();
        final String s1 = sc.next();
        sc.close();
        String result = "a";
        if (Character.isUpperCase(s1.charAt(0))) {
            result = "A";
        }
        System.out.println(result);
    }
}
