merge_sort.rb

array = [6,5,3,1,8,7,2,4]
pairs = []
new_pairs = []
newer_pairs = []

# BUILD PAIRS
(0..array.length - 1).step(2).each do |index|
  new_pairs << [array[index],array[index+1]]
end

# COMPARE AND SORT PAIRS
new_pairs.each do |pair|
  needs_flipping = (pair[0] <=> pair[1])
  if needs_flipping == 1
    old_val = pair[0]
    pair[0] = pair[1]
    pair[1] = old_val
    puts "We need to flip it. Now it's like this #{pair}."
  end
  new_pairs << pair
end

# COMPARE AND SORT PAIRS OF PAIRS
(0..new_pairs.length - 1).step(2).each do |index|
    new_pairs.each do |pair|
      p pair[index]
    needs_flipping = (pair[1][0] <=> pair[0][1])
    if needs_flipping == 1
      old_val = pair[0]
      pair[0] = pair[1]
      pair[1] = old_val
      puts "We need to flip it. Now it's like this #{pair}."
    end
    newer_pairs << pair
  end
end
puts "Newer pairs are: #{newer_pairs}"
puts "****************************************"