def build_upward as, i
  p_i = (i + 1) / 2 - 1
  if p_i >= 0 && as[p_i] < as[i]
    as[p_i], as[i] = as[i], as[p_i]
    build_upward as, p_i
  end
end

def build_downward as, i
  a_len = as.length
  l_i = 2 * (i + 1) - 1
  r_i = 2 * (i + 1)
  v = as[i]
  l_v = ((a_len - 1) >= l_i) ? as[l_i] : -1
  r_v = ((a_len - 1) >= r_i) ? as[r_i] : -1

  largest_i = i
  largest_v = as[i]
  if l_v > largest_v
    largest_i = l_i
    largest_v = l_v
  end
  if r_v > largest_v
    largest_i = r_i
    largest_v = r_v
  end
  if largest_i != i
    as[i], as[largest_i] = as[largest_i], as[i]
    build_downward as, largest_i
  end
end

heap = []
res = []
while l = gets
  command, val = l.chomp.split(' ')
  case command
  when 'end'
    puts res.join("\n")
    break
  when 'insert'
    heap << val.to_i
    build_upward heap, heap.length - 1
  when 'extract'
    res << heap[0]
    if heap.length > 1
      heap[0] = heap.pop
      build_downward heap, 0
    end
  end
end
