a_w, a_b = gets.split.map(&:to_i)
b_w, b_b = gets.split.map(&:to_i)
c, d = gets.split.map(&:to_i)
if a_b <= c
	b_b += a_b
	b_w += (c-a_b)
	a_w -= (c-a_b)
else
	b_b += c
end
if b_w <= d
	a_w += b_w
else
	a_w += d
end
puts a_w