title: Ceil function using limited set of arithmetic operators
body: <p>Is it possible to calculate a ceiling (e.g <code>ceil(2.12) = 3</code>) with only a few arithmetic operations available: <code>* - + /</code> 
  I.e. without casting and other software tricks, only using division/mul/sub/addition and comparison operators?</p>
  
  <p>Clarifications:</p>
  
  <ul>
  <li>Complexity is important, but I will be glad to hear any solutions.</li>
  <li>Modulus not available.</li>
  <li>Values are positive. </li>
  <li>Operations are not rounding.</li>
  <li>By software tricks I meant mod, bit level manipulations, etc.</li>
  </ul>
  
  <p>Basically I have a system which allows assigning expressions to variables where expression can contain only the above 4 arithmetic operation, comparisons, and loops. E.g.</p>
  
  <p>var x = if (A * (1.434 + 0.4325)) > 54.4534) then 45.6
      else then 43.435</p>
  
  <p>and I would like to do </p>
  
  <p>var x = CEIL(...)</p>