k = int(input())
a, x = list(map(int, input().split()))
b, y = list(map(int, input().split()))
if a == 0 and x == 0:
    r = y * max(k - b, 0)
elif a == 0 and b == 0:
    r = (x + y) * k
elif a == b:
    r = max(x, y) * max(k - a, 0) + min(x, y) * max(k - 2 * a, 0)
elif x == y:
    r = a * max(k - min(a, b), 0) + a * max(k - a - b, 0)
else:
    r1 = x * max(k - a, 0) + y * max(k - a - b, 0)
    r2 = y * max(k - b, 0) + x * max(k - a - b, 0)
    r = max(r1, r2)

print(r)