compress.rb

def compress(sequence)
  array = sequence.split
  hash = Hash.new(0)
  second_hash = Hash.new(0)

  array.each_with_index do |item, i|
    if hash[item] != 0 && array[i-1] != item 
      second_hash[item] += 1
    else
      hash[item] += 1
    end
  end
  output(hash, second_hash)
end

def output(hash, second_hash)
  hash.each do |k, v|
    print "#{v} #{k} "
  end
  second_hash.each do |k, v|
    print "#{v} #{k}"
  end
  puts
end

compress("40 40 40 40 29 29 29 29 29 29 29 29 57 57 92 92 92 92 92 86 86 86 86 86 86 86 86 86 86")
compress("73 73 73 73 41 41 41 41 41 41 41 41 41 41")
compress("1 1 3 3 3 2 2 2 2 14 14 14 11 11 11 2")
compress("7")

#output 
#4 40 8 29 2 57 5 92 10 86
#4 73 10 41
#2 1 3 3 4 2 3 14 3 11 1 2
#1 7