Aw, Ab = map(int, input().split())

Bw, Bb = map(int, input().split())

C, D = map(int, input().split())

Aw, Ab, Bw, Bb = Aw - max(0, C - Ab), max(0, Ab - C), Bw + max(0, C - Ab), Bb + min(C, Ab)

print(Aw + min(D, Bw))