#!/usr/bin/env python

from operator import itemgetter

tawe = []
tawe.append(tuple(['A'] + [int(x) for x in input().split()]))
tawe.append(tuple(['B'] + [int(x) for x in input().split()]))
tawe.append(tuple(['C'] + [int(x) for x in input().split()]))

tawe = sorted(tawe, key=itemgetter(2))
tawe = sorted(tawe, key=itemgetter(1), reverse=True)

for name in tawe:
    print(name[0])