L = [list(map(int,input().split())) for i in range(3)]
L[0].append("A")
L[1].append("B")
L[2].append("C")

L = sorted(L, key=lambda x : x[1], reverse=False)
L = sorted(L, key=lambda x : x[0], reverse=True)
for i in range(3) :
    print(L[i][2])