loop do
  n,m = gets.split.map(&:to_i)
  break if (n|m)==0
  ps = gets.split.map(&:to_i)
  ps.sort!{|a,b| b-a}
  ans = ps.inject(0){|sum,x| sum+x}
  i = 0
  while i < ps.size
    a = ps.slice(i,m)
    ans -=a[1] if a.size ==m
    i += m
  end
  puts ans
end