import sys
input = sys.stdin.readline
def read_values(): return tuple(map(int, input().split()))
def main():
    N = int(input())
    A = [0] * 3
    B = [0] * 3
    for i in range(3):
        A[i], B[i] = read_values()

    if A[1] * B[2] < A[2] * B[1]:
        A[1], A[2], B[1], B[2] = A[2], A[1], B[2], B[1]

    if A[0] * B[2] < A[2] * B[0]:
        A[0], A[2], B[0], B[2] = A[2], A[0], B[2], B[0]

    print(max(((N - i * A[0] - j * A[1]) // A[2]) * B[2] + i * B[0] + j * B[1] for i in range(min(A[2], N // A[0] + 1)) for j in range(min(A[2], (N - i * A[0]) // A[1] + 1))))

if __name__ == "__main__":
    main()