import java.io.FileNotFoundException;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	String a = sc.next();

    	if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	}


    }
} import java.io.FileNotFoundException; FileNotFoundException java.io import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	String a = sc.next();

    	if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	}


    }
} Main public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	String a = sc.next();

    	if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	}


    } main {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	String a = sc.next();

    	if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	}


    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String a = sc.next(); a sc.next() sc.next sc if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	} Character.isUpperCase(a.charAt(0)) Character.isUpperCase Character a.charAt(0) a.charAt a 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) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	String a = sc.next();

    	if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	}


    }
} public class Main {
    public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	String a = sc.next();

    	if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	}


    }
} Main
import java.io.FileNotFoundException;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws FileNotFoundException {

//    	File file = new File("src/in.txt");

        //コード
//    	Scanner sc = new Scanner(file);
    	Scanner sc = new Scanner(System.in);

    	String a = sc.next();

    	if(Character.isUpperCase(a.charAt(0))) {
    		System.out.println("A");
    	} else {
    		System.out.println("a");
    	}


    }
}