

import java.util.*;
import java.lang.*;
import java.io.*;


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


import java.util.*;
import java.lang.*;
import java.io.*;


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