a = [10, 0, 7, 8, 5, 4, 2, 1, 3, 6, 9]
swp = 100
length = a.length - 1

for i in 0.upto(a.length - 1)
  for j in 0.upto(a.length - 1)
    if a[i] > a[j]
      swp = a[i]
      a[i] = a[j]
      a[j] = swp
    end
    j += 1
  end
  i += 1
end
puts a