/*
package com.company.practice;
*/

import java.util.Scanner;
import java.lang.*;
import java.util.Scanner;

import static java.lang.Character.isUpperCase;

public class Main {
    public static void main(String[] args)
    {
        Scanner key = new Scanner(System.in);
        char s = key.next().charAt(0);
        if(isUpperCase(s))
            System.out.println("A");
        else
            System.out.println("a");
    }
} import java.util.Scanner; Scanner java.util import java.lang.*; lang.* java import java.util.Scanner; Scanner java.util import static java.lang.Character.isUpperCase; import static java.lang.Character.isUpperCase; import static java.lang.Character.isUpperCase; public class Main {
    public static void main(String[] args)
    {
        Scanner key = new Scanner(System.in);
        char s = key.next().charAt(0);
        if(isUpperCase(s))
            System.out.println("A");
        else
            System.out.println("a");
    }
} Main public static void main(String[] args)
    {
        Scanner key = new Scanner(System.in);
        char s = key.next().charAt(0);
        if(isUpperCase(s))
            System.out.println("A");
        else
            System.out.println("a");
    } main {
        Scanner key = new Scanner(System.in);
        char s = key.next().charAt(0);
        if(isUpperCase(s))
            System.out.println("A");
        else
            System.out.println("a");
    } Scanner key = new Scanner(System.in); key new Scanner(System.in) char s = key.next().charAt(0); s key.next().charAt(0) key.next().charAt key.next() key.next key 0 if(isUpperCase(s))
            System.out.println("A");
        else
            System.out.println("a"); isUpperCase(s) isUpperCase s 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 public class Main {
    public static void main(String[] args)
    {
        Scanner key = new Scanner(System.in);
        char s = key.next().charAt(0);
        if(isUpperCase(s))
            System.out.println("A");
        else
            System.out.println("a");
    }
} public class Main {
    public static void main(String[] args)
    {
        Scanner key = new Scanner(System.in);
        char s = key.next().charAt(0);
        if(isUpperCase(s))
            System.out.println("A");
        else
            System.out.println("a");
    }
} Main
/*
package com.company.practice;
*/

import java.util.Scanner;
import java.lang.*;
import java.util.Scanner;

import static java.lang.Character.isUpperCase;

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