input = gets.chomp.split(" ").map(&:to_i)
prices = gets.chomp.split(" ").map(&:to_i).sort.reverse
result = []
result << (prices.shift /2)

(input[0]-1).times do 
  if prices.first >= result.first
    result << (prices.shift/2)
  else
    result << result.shift/2
  end
end
sum = 0
prices.each do |e|
  sum += e
end
result.each do |e|
  sum += e
end
puts sum