list2=["A","B","C"]
list1=[]
for i in range(3):
    line=input()
    line=line.rstrip().split(" ")
    list1.append([int(line[0]),100-int(line[1]),list2[i]])
list1.sort(reverse=True)
#print(list1)
for j in range(3):
    print(list1[j][2])