xs=readlines.map(&:to_i).sort.reverse
ac=xs[2..6].inject :*

def c2(n)
  n*(n-1)/2
end

def f(a,b)
  r = (b/2) * (b - b/2)
  m = 0
  for k in 1..a
    m = [c2(a-k) * k, m].max
  end
  r * m
end

p [f(xs[0],xs[1]) , f(xs[1],xs[0]) ].max * ac