import java.util.*;
public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char ch = sc.next().charAt(0);
    if(ch >=65 && ch<=90) {
      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);
    char ch = sc.next().charAt(0);
    if(ch >=65 && ch<=90) {
      System.out.println("A");
    } else {
      System.out.println("a");
    }
  }
} Main public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char ch = sc.next().charAt(0);
    if(ch >=65 && ch<=90) {
      System.out.println("A");
    } else {
      System.out.println("a");
    }
  } main {
    Scanner sc = new Scanner(System.in);
    char ch = sc.next().charAt(0);
    if(ch >=65 && ch<=90) {
      System.out.println("A");
    } else {
      System.out.println("a");
    }
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) char ch = sc.next().charAt(0); ch sc.next().charAt(0) sc.next().charAt sc.next() sc.next sc 0 if(ch >=65 && ch<=90) {
      System.out.println("A");
    } else {
      System.out.println("a");
    } ch >=65 && ch<=90 ch >=65 ch 65 ch<=90 ch 90 {
      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);
    char ch = sc.next().charAt(0);
    if(ch >=65 && ch<=90) {
      System.out.println("A");
    } else {
      System.out.println("a");
    }
  }
} public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    char ch = sc.next().charAt(0);
    if(ch >=65 && ch<=90) {
      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);
    char ch = sc.next().charAt(0);
    if(ch >=65 && ch<=90) {
      System.out.println("A");
    } else {
      System.out.println("a");
    }
  }
}