import sys
input = sys.stdin.readline

N = int(input())
A1, B1 = map(int, input().split())
A2, B2 = map(int, input().split())
A3, B3 = map(int, input().split())
D = 0
for x1 in range(min(A2, A3)+1):
    for x2 in range(min(A1, A3)+1):
        remN = N-A1*x1-A2*x2
        if remN < 0:
            break
        D = max(D, B1*x1+B2*x2+B3*(remN//A3))

for x3 in range(min(A2, A1)+1):
    for x2 in range(min(A1, A3)+1):
        remN = N-A3*x3-A2*x2
        if remN < 0:
            break
        D = max(D, B1*(remN//A1)+B2*x2+B3*x3)

for x3 in range(min(A2, A1)+1):
    for x1 in range(min(A2, A3)+1):
        remN = N-A3*x3-A1*x1
        if remN < 0:
            break
        D = max(D, B1*x1+B2*(remN//A2)+B3*x3)

print(D)