import java.util.*;

public class Main {
 
  public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);
    
    String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String lowerCases = "abcdefghijklmnopqrstuvwxyz";
    
    String oneChar = sc.next();
    if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    }
  }
} import java.util.*; util.* java public class Main {
 
  public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);
    
    String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String lowerCases = "abcdefghijklmnopqrstuvwxyz";
    
    String oneChar = sc.next();
    if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    }
  }
} Main public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);
    
    String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String lowerCases = "abcdefghijklmnopqrstuvwxyz";
    
    String oneChar = sc.next();
    if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    }
  } main {
    
    Scanner sc = new Scanner(System.in);
    
    String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String lowerCases = "abcdefghijklmnopqrstuvwxyz";
    
    String oneChar = sc.next();
    if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    }
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; upperCases "ABCDEFGHIJKLMNOPQRSTUVWXYZ" String lowerCases = "abcdefghijklmnopqrstuvwxyz"; lowerCases "abcdefghijklmnopqrstuvwxyz" String oneChar = sc.next(); oneChar sc.next() sc.next sc if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    } upperCases.indexOf(oneChar) >= 0 upperCases.indexOf(oneChar) upperCases.indexOf upperCases oneChar 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" String[] args args public class Main {
 
  public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);
    
    String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String lowerCases = "abcdefghijklmnopqrstuvwxyz";
    
    String oneChar = sc.next();
    if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    }
  }
} public class Main {
 
  public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);
    
    String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String lowerCases = "abcdefghijklmnopqrstuvwxyz";
    
    String oneChar = sc.next();
    if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    }
  }
} Main
import java.util.*;

public class Main {
 
  public static void main(String[] args) {
    
    Scanner sc = new Scanner(System.in);
    
    String upperCases = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    String lowerCases = "abcdefghijklmnopqrstuvwxyz";
    
    String oneChar = sc.next();
    if (upperCases.indexOf(oneChar) >= 0) {
       System.out.println("A");
    } else {
       System.out.println("a");
    }
  }
}