import sys # sys.setrecursionlimit(200005) int1 = lambda x: int(x)-1 pDB = lambda *x: print(*x, end="\n", file=sys.stderr) p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr) def II(): return int(sys.stdin.readline()) def LI(): return list(map(int, sys.stdin.readline().split())) def LLI(rows_number): return [LI() for _ in range(rows_number)] def LI1(): return list(map(int1, sys.stdin.readline().split())) def LLI1(rows_number): return [LI1() for _ in range(rows_number)] def SI(): return sys.stdin.readline().rstrip() # dij = [(0, 1), (-1, 0), (0, -1), (1, 0)] dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)] inf = (1 << 63)-1 # inf = (1 << 31)-1 md = 10**9+7 # md = 998244353 def binary_search(l, r, minimize): if minimize: l -= 1 else: r += 1 while l+1 < r: m = (l+r)//2 if ok(m) ^ minimize: l = m else: r = m if minimize: return r return l def ok(b): return min(a*la, h)*min(w, b*lb)+a*ka+b*kb >= h*w h, w, la, lb, ka, kb = LI() mx = (h+la-1)//la+(w+lb-1)//lb ans = inf for a in range(mx+1): b = binary_search(0, mx, True) ans = min(ans, a+b) print(ans)