gistfile1.php

function add_classical($nr1, $nr2, $type='decimal'){
  $sum = NULL;
  switch($type){
  case 'decimal':
    $sum = (int)$nr1 + (int)$nr2;
  case 'binary':
    $sum = bindec($nr1) + bindec($nr2);
  }
  return $sum;
}