#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]

    ans=0
    for i in range(A[2]):
        for j in range(A[2]):
            use = i*A[0]+j*A[1]
            if use>N:
                break
            ans=max(ans,i*B[0]+j*B[1]+(N-use)//A[2]*B[2])
    print(ans)
    
if __name__ == "__main__":
    main()