sa, pa, xa = input().split()
sb, pb, xb = input().split()
if len(pa) > len(pb):
    print(sa)
    exit()
elif len(pa) < len(pb):
    print(sb)
    exit()
pa = int(pa)
pb = int(pb)
if pa > pb:
    print(sa)
elif pa < pb:
    print(sb)
else:
    print(-1)