發送短信 : Revisiting a Number-Theoretic Puzzle: The Census-Taker Problem

  _____    __   __   _    _    _    _    _    _   
 / ____||  \ \\/ // | || | || | || | || | || | || 
/ //---`'   \ ` //  | || | || | || | || | || | || 
\ \\___      | ||   | \\_/ || | \\_/ || | \\_/ || 
 \_____||    |_||    \____//   \____//   \____//  
  `----`     `-`'     `---`     `---`     `---`