title: What is the use of ## preprocessor in C
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/1489932/c-preprocessor-and-concatenation">C preprocessor and concatenation</a>  </p>
  </blockquote>
  
  
  
  <p>can anybody explain with example ?</p>