import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

from operator import itemgetter

data = []
for key in 'ABC':
    ht, wt = map(int, readline().split())
    data.append((ht, wt, key))

data.sort(key = itemgetter(1))
data.sort(key = itemgetter(0), reverse=True)

answer = map(itemgetter(2), data)
print('\n'.join(answer))