import java.util.*;
import java.io.*;
class Main
{
    public static void main(String args[])throws IOException
    {
        char ch;
        ch=(char)System.in.read();
        if(Character.isUpperCase(ch))
            System.out.println("A");
        else
            System.out.println("a");
    }
} import java.util.*; util.* java import java.io.*; io.* java class Main
{
    public static void main(String args[])throws IOException
    {
        char ch;
        ch=(char)System.in.read();
        if(Character.isUpperCase(ch))
            System.out.println("A");
        else
            System.out.println("a");
    }
} Main public static void main(String args[])throws IOException
    {
        char ch;
        ch=(char)System.in.read();
        if(Character.isUpperCase(ch))
            System.out.println("A");
        else
            System.out.println("a");
    } main {
        char ch;
        ch=(char)System.in.read();
        if(Character.isUpperCase(ch))
            System.out.println("A");
        else
            System.out.println("a");
    } char ch; ch ch=(char)System.in.read() ch (char)System.in.read() System.in.read System.in System System.in if(Character.isUpperCase(ch))
            System.out.println("A");
        else
            System.out.println("a"); Character.isUpperCase(ch) Character.isUpperCase Character ch System.out.println("A") System.out.println System.out System System.out "A" System.out.println("a") System.out.println System.out System System.out "a" String args[] args
import java.util.*;
import java.io.*;
class Main
{
    public static void main(String args[])throws IOException
    {
        char ch;
        ch=(char)System.in.read();
        if(Character.isUpperCase(ch))
            System.out.println("A");
        else
            System.out.println("a");
    }
}
