R,P,Q = map(int,input().split())
A,B,C,D = map(int,input().split())

ok = 0
ng = 1 + (A+B+C+D) // 3
while ng - ok > 1:
    mid = (ok + ng) // 2
    
    color_change = max(0,mid - A) + max(0, mid - B) + max(0, mid - C)
    cost = P * mid + Q * color_change

    if cost <= R:
        ok = mid
    else:
        ng = mid

print(ok)