title: Grade Sudoku difficulty level
body: <p>I am building a Sudoku game for fun, written in Javascript.<br/>
  Everything works fine, board is generated completely with a single solution each time.</p>
  
  <p>My only <strong>problem</strong> is, and this is what's keeping me from having my project released to public<br/>
  is that I don't know how to grade my boards for difficulty levels. I've looked EVERYWHERE,<br/>
  posted on forums, etc. I don't want to write the algorithms myself, thats not the point of this
  project,<br/>and beside, they are too complex for me, as i am no mathematician.</p>
  
  <p>The only thing i came close to was is <a href="http://www.sudokuwiki.org/sudoku.htm" rel="noreferrer">this website that does grading via JS</a><br/>but the problem is, the code is written in such a lousy undocumented, very ad-hoc manner,<br/>therefor cannot be borrowed...</p>
  
  <p>I'll come to the point -<br/>Can anyone please point me to a place which offers a source code for Sudoku grading/rating?</p>
  
  <p>Thanks</p>
  
  <p><strong>Update 22.6.11:</strong><br/>
  This is my <a href="http://www.sudokubum.com" rel="noreferrer">Sudoku game</a>, and I've implemented my own grading system which relies<br/>
  on basic human logic solving techniques, so check it out.</p>