d,e,h,l,o,r,w = STDIN.map(&:to_i).values_at(3,4,7,11,14,17,22)
if d < 1 || e < 1 || h < 1 || l < 3 || o < 2 || r < 1 || w < 1
    p 0
else
    ans = 0
    2.upto(l - 1){|a|
        ans = [ans, a * (a - 1) / 2 * (l - a)].max
        }
    p d * e * h * r * w * (o / 2) * (o - o / 2) * ans
end