import java.util.Comparator;
import java.util.Scanner;
import java.util.stream.Stream;

public class Main{
	static Scanner s=new Scanner(System.in);
	static int getInt(){return Integer.parseInt(s.next());}

	public static void main(String[] $){
		int[]v= {getInt(),getInt(),getInt()};
		Stream.of('A','B','C').sorted(Comparator.comparingInt(o->-v[o-'A'])).forEach(System.out::println);
	}
}