n = gets.to_i
s = gets.split.map(&:to_i)
n.downto(3){|i|
    s[i - 2] += s[i]
    s[i] = 0
    }
d = 0
ans = 0
([n,2].min).downto(0){|i|
    if s[i] != 0
        d = i
        ans = s[0..i].join(' ')
        break
    end
    }
p d
puts ans