title: Shell function does not return values greater than 255
body: <pre><code>   sum()
    {
       return $(($1+$2))
  
    }
  
     read a b
     sum $a $b
     echo $?
  </code></pre>
  
  <p>when we pass the value for a=255 and for b=36 the ans will be 35 why?</p>