func_code: def swap(a, i, j):
      tmp = a[j]
      a[j] = a[i]
      a[i] = tmp
  
  
  def reverse(a):
      i = 0
      n = len(a) - 1
      while n < len(a) / 2:
          if a[j] < a[n]:
              swap(a, i, j)
          n = n + 1