Problem of the Day
A new programming or logic puzzle every Mon-Fri

We're going way back for this one. Today's problem is creating a digital typewritter. When the program is run it will allow the user to enter text. When the user hits enter that line will be saved to a text file. The program runs until the following combination occurs: blank line > enter > "." > enter.

Bonus Round

• Open the file after the user is done inputting text (after the blank line > enter > "." > enter has occurred)
• Limit the number of characters per line to 72

Comments:

• Pegleg - 10 years, 8 months ago

  Good moring everyone, Python 3.4

  import webbrowser
  
  paper = open('Paper.txt','a+')
  blank_line = True
  period = True
  
  while period:
      user_input = input('Line check')
      if len(user_input)> 72:
          print('Error! Text fell off page TRUNCATED')
          user_input = user_input[:72]
      if not user_input:
          blank_line = False
      if not blank_line and user_input=='.':
          period = False
          break
      paper.write(user_input+'\n')
  
  webbrowser.open("Paper.txt")
  

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• Anonymous - 10 years, 8 months ago

  blank_line should be checked and reset at the end of your loop, else the exit combination doesn't have to happen consecutively

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• Hueho - 10 years, 8 months ago

  Dunno if the CLI open is avaiable anywhere outside Mac OS, but here we go:

  $file_name = ARGV.first
  
  FINISH = "."
  
  def read
    line = STDIN.gets(72)
    if line.strip.empty?
      read_next line
    else
      line
    end
  end
  
  def read_next(prev)
    result = prev
    loop do
      line = STDIN.gets(72)
      if line.strip.empty?
        result += line
      elsif line.strip == FINISH
        return nil
      else
        return result + line
      end
    end
  end
  
  while data = read
    open($file_name, "a") do |io|
      io << data
    end
  end
  
  system("open #{$file_name}")
  

  Also adding a byte limit in gets is not working for some reason. :(

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• Walker Crouse - 10 years, 8 months ago

  It varies on different platforms, for instance Ubuntu and it's flavors use "see <file>".

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• Walker Crouse - 10 years, 8 months ago

  Short but sweet Py

  from subprocess import call
  
  
  def addln(ln):
      with open("doc.out", 'a') as file:
          file.write(ln + "\n")
          file.close()
      return ln
  
  
  MAX_LN_LEN = 72
  
  
  def main():
      lines = []
      while True:
          lines_amt = len(lines)
          if lines_amt >= 3 and lines[lines_amt-1] == "" and lines[lines_amt-2] == "." and lines[lines_amt-3] == "":
              call("see doc.txt".split())
              break
          ln = raw_input(">: ")
          if len(ln) > MAX_LN_LEN:
              print("line too long (max " + str(MAX_LN_LEN) + ")")
              continue
          ln = "" if ln is None else ln
          lines.append(addln(ln))
  
  
  if __name__ == "__main__":
      main()
  

  Output

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