N = gets.to_i A = gets.split.map(&:to_i) nums = [] A.each.with_index(1) do |a, i| nums << [a, i] end nums.sort_by! { |a, _| a } ans = [] nums.each.with_index do |(a, i), idx| if idx.even? ans.push(i) else ans.unshift(i) end end while ans[0] != 1 ans.rotate! end ans << 1 puts ans.join(' ')