
import java.util.Map.Entry;
import java.util.*;
import java.math.*;
import org.w3c.dom.css.Counter;
  
public class Main{
    public static void main(final String[] args){
       
        final Scanner sc = new Scanner(System.in);
        //int N =sc.nextInt();
        //ArrayList<Integer>  allmen =new ArrayList <Integer>();
        //HashSet doubled =new HashSet<Integer>();
        String str = sc.next();
        if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        }
        //System.out.println(ans);
    }
} import java.util.Map.Entry; Entry java.util.Map import java.util.*; util.* java import java.math.*; math.* java import org.w3c.dom.css.Counter; Counter org.w3c.dom.css public class Main{
    public static void main(final String[] args){
       
        final Scanner sc = new Scanner(System.in);
        //int N =sc.nextInt();
        //ArrayList<Integer>  allmen =new ArrayList <Integer>();
        //HashSet doubled =new HashSet<Integer>();
        String str = sc.next();
        if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        }
        //System.out.println(ans);
    }
} Main public static void main(final String[] args){
       
        final Scanner sc = new Scanner(System.in);
        //int N =sc.nextInt();
        //ArrayList<Integer>  allmen =new ArrayList <Integer>();
        //HashSet doubled =new HashSet<Integer>();
        String str = sc.next();
        if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        }
        //System.out.println(ans);
    } main {
       
        final Scanner sc = new Scanner(System.in);
        //int N =sc.nextInt();
        //ArrayList<Integer>  allmen =new ArrayList <Integer>();
        //HashSet doubled =new HashSet<Integer>();
        String str = sc.next();
        if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        }
        //System.out.println(ans);
    } final Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String str = sc.next(); str sc.next() sc.next sc if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        } Character.isUpperCase( str.charAt( 0 ) ) Character.isUpperCase Character str.charAt( 0 ) str.charAt str 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" final String[] args args public class Main{
    public static void main(final String[] args){
       
        final Scanner sc = new Scanner(System.in);
        //int N =sc.nextInt();
        //ArrayList<Integer>  allmen =new ArrayList <Integer>();
        //HashSet doubled =new HashSet<Integer>();
        String str = sc.next();
        if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        }
        //System.out.println(ans);
    }
} public class Main{
    public static void main(final String[] args){
       
        final Scanner sc = new Scanner(System.in);
        //int N =sc.nextInt();
        //ArrayList<Integer>  allmen =new ArrayList <Integer>();
        //HashSet doubled =new HashSet<Integer>();
        String str = sc.next();
        if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        }
        //System.out.println(ans);
    }
} Main

import java.util.Map.Entry;
import java.util.*;
import java.math.*;
import org.w3c.dom.css.Counter;
  
public class Main{
    public static void main(final String[] args){
       
        final Scanner sc = new Scanner(System.in);
        //int N =sc.nextInt();
        //ArrayList<Integer>  allmen =new ArrayList <Integer>();
        //HashSet doubled =new HashSet<Integer>();
        String str = sc.next();
        if( Character.isUpperCase( str.charAt( 0 ) ) ) {
            System.out.println( "A" );
        }
        else {
            System.out.println( "a" );
        }
        //System.out.println(ans);
    }
}