import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Person[] persons = new Person[3];
        for (int i = 0; i < 3; i++) {
            persons[i] = new Person((char)(i + 'A'), sc.nextInt(), sc.nextInt());
        }
        Arrays.sort(persons);
        for (int i = 0; i < 3; i++) {
            System.out.println(persons[i].id);
        }
   }
   
   static class Person implements Comparable<Person> {
       char id;
       int height;
       int weight;
       public Person (char id, int height, int weight) {
           this.id = id;
           this.height = height;
           this.weight = weight;
       }
       
       public int compareTo(Person another) {
           if (height == another.height) {
               return weight - another.weight;
           } else {
               return another.height - height;
           }
       }
       
   }
}