H, W, LA, LB, KA, KB = map(int, input().split())

ans = 1<<60
if 1 <= KB: ans = min(ans, (H*W+KB-1)//KB)
if 1 <= KA: ans = min(ans, (H*W+KA-1)//KA)

for h in range(1, H+W+1):
    left = -1
    right = (W+LB-1)//LB+1
    while left+1 < right:
        mid = (left+right)//2
        if min(LA*h, H)*min(LB*mid, W)+KA*h+KB*mid < H*W:
            left = mid
        else:
            right = mid
    if H*W <= min(LA*h, H)*min(LB*right, W)+KA*h+KB*right:
        ans = min(ans, h+right)
for w in range(1, H+W+1):
    left = -1
    right = (H+LA-1)//LA+1
    while left+1 < right:
        mid = (left+right)//2
        if min(LA*mid, H)*min(LB*w, W)+KA*mid+KB*w < H*W:
            left = mid
        else:
            right = mid
    if H*W <= min(LA*right, H)*min(LB*w, W)+KA*right+KB*w:
        ans = min(ans, right+w)

print(ans)