import java.util.*;
import java.io.*;

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

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        OutputStreamWriter osw = new OutputStreamWriter(System.out);
        PrintWriter out = new PrintWriter(osw);
    
        String s = br.readLine();
        char[] alpha = s.toCharArray();
    
        if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        }
        out.close();
        
    }
} import java.util.*; util.* java import java.io.*; io.* java public class Main {
    public static void main(String[] args) throws Exception {

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        OutputStreamWriter osw = new OutputStreamWriter(System.out);
        PrintWriter out = new PrintWriter(osw);
    
        String s = br.readLine();
        char[] alpha = s.toCharArray();
    
        if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        }
        out.close();
        
    }
} Main public static void main(String[] args) throws Exception {

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        OutputStreamWriter osw = new OutputStreamWriter(System.out);
        PrintWriter out = new PrintWriter(osw);
    
        String s = br.readLine();
        char[] alpha = s.toCharArray();
    
        if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        }
        out.close();
        
    } main {

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        OutputStreamWriter osw = new OutputStreamWriter(System.out);
        PrintWriter out = new PrintWriter(osw);
    
        String s = br.readLine();
        char[] alpha = s.toCharArray();
    
        if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        }
        out.close();
        
    } InputStreamReader isr = new InputStreamReader(System.in); isr new InputStreamReader(System.in) BufferedReader br = new BufferedReader(isr); br new BufferedReader(isr) OutputStreamWriter osw = new OutputStreamWriter(System.out); osw new OutputStreamWriter(System.out) PrintWriter out = new PrintWriter(osw); out new PrintWriter(osw) String s = br.readLine(); s br.readLine() br.readLine br char[] alpha = s.toCharArray(); alpha s.toCharArray() s.toCharArray s if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        } Character.isUpperCase(alpha[0]) Character.isUpperCase Character alpha[0] alpha 0 {
            out.println("A");
        } out.println("A") out.println out "A" {
            out.println("a");
        } out.println("a") out.println out "a" out.close() out.close out String[] args args public class Main {
    public static void main(String[] args) throws Exception {

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        OutputStreamWriter osw = new OutputStreamWriter(System.out);
        PrintWriter out = new PrintWriter(osw);
    
        String s = br.readLine();
        char[] alpha = s.toCharArray();
    
        if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        }
        out.close();
        
    }
} public class Main {
    public static void main(String[] args) throws Exception {

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        OutputStreamWriter osw = new OutputStreamWriter(System.out);
        PrintWriter out = new PrintWriter(osw);
    
        String s = br.readLine();
        char[] alpha = s.toCharArray();
    
        if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        }
        out.close();
        
    }
} Main
import java.util.*;
import java.io.*;

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

        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        OutputStreamWriter osw = new OutputStreamWriter(System.out);
        PrintWriter out = new PrintWriter(osw);
    
        String s = br.readLine();
        char[] alpha = s.toCharArray();
    
        if(Character.isUpperCase(alpha[0])){
            out.println("A");
        }else{
            out.println("a");
        }
        out.close();
        
    }
}
