Ha,Wa=map(int,input().split())
Hb,Wb=map(int,input().split())
Hc,Wc=map(int,input().split())
a=[Ha*100-Wa,"A"]
b=[Hb*100-Wb,"B"]
c=[Hc*100-Wc,"C"]
l=sorted([a,b,c])[::-1]
for i in range(3):
    print(l[i][1])