import java.util.*;
class Main {
 public static void main(String[] args) {
   Scanner scan = new Scanner(System.in);
   String str = scan.nextLine();
   if(str == str.toUpperCase()) {
   	System.out.println('A');
   } else {
    System.out.println('a');
   }
 }
} import java.util.*; util.* java class Main {
 public static void main(String[] args) {
   Scanner scan = new Scanner(System.in);
   String str = scan.nextLine();
   if(str == str.toUpperCase()) {
   	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.nextLine();
   if(str == str.toUpperCase()) {
   	System.out.println('A');
   } else {
    System.out.println('a');
   }
 } main {
   Scanner scan = new Scanner(System.in);
   String str = scan.nextLine();
   if(str == str.toUpperCase()) {
   	System.out.println('A');
   } else {
    System.out.println('a');
   }
 } Scanner scan = new Scanner(System.in); scan new Scanner(System.in) String str = scan.nextLine(); str scan.nextLine() scan.nextLine scan if(str == str.toUpperCase()) {
   	System.out.println('A');
   } else {
    System.out.println('a');
   } str == str.toUpperCase() str str.toUpperCase() str.toUpperCase str {
   	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
import java.util.*;
class Main {
 public static void main(String[] args) {
   Scanner scan = new Scanner(System.in);
   String str = scan.nextLine();
   if(str == str.toUpperCase()) {
   	System.out.println('A');
   } else {
    System.out.println('a');
   }
 }
}