import java.util.*;
 class Main{
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        char s=sc.nextLine().toCharArray()[0];
        boolean b=Character.isLowerCase(s);
        if(b){
            System.out.println("a");
        }
        else{
            System.out.println("A");
        }
    }
    
} import java.util.*; util.* java class Main{
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        char s=sc.nextLine().toCharArray()[0];
        boolean b=Character.isLowerCase(s);
        if(b){
            System.out.println("a");
        }
        else{
            System.out.println("A");
        }
    }
    
} Main public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        char s=sc.nextLine().toCharArray()[0];
        boolean b=Character.isLowerCase(s);
        if(b){
            System.out.println("a");
        }
        else{
            System.out.println("A");
        }
    } main {
        Scanner sc=new Scanner(System.in);
        char s=sc.nextLine().toCharArray()[0];
        boolean b=Character.isLowerCase(s);
        if(b){
            System.out.println("a");
        }
        else{
            System.out.println("A");
        }
    } Scanner sc=new Scanner(System.in); sc new Scanner(System.in) char s=sc.nextLine().toCharArray()[0]; s sc.nextLine().toCharArray()[0] sc.nextLine().toCharArray() sc.nextLine().toCharArray sc.nextLine() sc.nextLine sc 0 boolean b=Character.isLowerCase(s); b Character.isLowerCase(s) Character.isLowerCase Character s if(b){
            System.out.println("a");
        }
        else{
            System.out.println("A");
        } b {
            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
import java.util.*;
 class Main{
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        char s=sc.nextLine().toCharArray()[0];
        boolean b=Character.isLowerCase(s);
        if(b){
            System.out.println("a");
        }
        else{
            System.out.println("A");
        }
    }
    
}