N = int(input())
AB = [list(map(int, input().split())) for _ in range(3)]

XAB = [[AB[i][1] / AB[i][0], AB[i][0], AB[i][1]] for i in range(len(AB))]
XAB.sort()

_, Ai, Bi = XAB[0]
_, Aj, Bj = XAB[1]
_, Ak, Bk = XAB[2]

ans = 0
for i in range(2000):
    for j in range(2000):
        if N - Ai * i - Aj * j < 0:
            continue
        k = (N - (Ai * i + Ai * j)) // Ak
        ans = max(ans, Bi * i + Bj * j, Bk * k)
print(ans)