import java.util.*;

public class Main{
public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    String str = scan.next();
    
    scan.close();
    if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    }
}
} import java.util.*; util.* java public class Main{
public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    String str = scan.next();
    
    scan.close();
    if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    }
}
} Main public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    String str = scan.next();
    
    scan.close();
    if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    }
} main {
    Scanner scan = new Scanner(System.in);
    String str = scan.next();
    
    scan.close();
    if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    }
} Scanner scan = new Scanner(System.in); scan new Scanner(System.in) String str = scan.next(); str scan.next() scan.next scan scan.close() scan.close scan if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    } 'A' <= str.charAt(0) && str.charAt(0) <= 'Z' 'A' <= str.charAt(0) 'A' str.charAt(0) str.charAt str 0 str.charAt(0) <= 'Z' str.charAt(0) str.charAt str 0 'Z' {
        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" String[] args args public class Main{
public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    String str = scan.next();
    
    scan.close();
    if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    }
}
} public class Main{
public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    String str = scan.next();
    
    scan.close();
    if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    }
}
} Main
import java.util.*;

public class Main{
public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    String str = scan.next();
    
    scan.close();
    if ('A' <= str.charAt(0) && str.charAt(0) <= 'Z') {
        System.out.println("A");
    } else {
        System.out.println("a");
    }
}
}
