N = int(input())
M = min(4000000,N)
DP = [- 10**9]*(M+1)
DP[0] = 0
A = [list(map(int,input().split())) for i in range(3)]
A = [(b/a,a,b) for a,b in A]

A.sort(key=lambda x:x[0])

_,a,b = A[0]

i = 1
while a*i <= M:
    DP[a*i] = b*i
    i+=1

_,a,b = A[1]
ans = 0
for i in range(M+1):
    if i>=a:
        DP[i] = max(DP[i-a]+b,DP[i])
    ans = max(ans,((N-i)//A[2][1])*A[2][2]+DP[i])

print(ans)