N = gets.to_i
A = gets.split.map(&:to_i)

zero_count = [0]
A.each do |x|
    zero_count << zero_count[-1] + (x == 0 ? 1 : 0)
end

ans = 0
N.times do |l|
    ac = l
    wa = N + 1
    while wa - ac > 1
        wj = (ac + wa) / 2
        if zero_count[wj] <= zero_count[l]
            ac = wj
        else
            wa = wj
        end
    end
    ans += N - ac
end

puts ans