old_contents: def main():
      def n31(a):# a = initial number
          c = 0
          l = [a]
          while a != 1:
              if a % 2 == 0:#if even divide it by 2
                  a = a // 2
              elif a % 2 == 1:#if odd 3n+1
                  a = 3*a +1
              c += 1#counter
              l += [a]
  
          return l , c
      print(n31(43))
      print(n31(98)[0][-1])# = a
      print("It took {0} steps.".format(n31(13))[1]))#optional finish
  
  if __name__ == '__main__':
      main()
  
new_contents: def main():
      def n31(a):# a = initial number
          c = 0
          l = [a]
          while a != 1:
              if a % 2 == 0:#if even divide it by 2
                  a = a // 2
              elif a % 2 == 1:#if odd 3n+1
                  a = 3*a +1
              c += 1#counter
              l += [a]
  
          return l , c
      print(n31(43))
      print(n31(98)[0][-1])# = a
      print("It took {0} steps.".format(n31(13)[1]))#optional finish
  
  if __name__ == '__main__':
      main()
  
subject: Update 3n+1.py