<?php


class Overload{
    const pi = 3.141432;
        
    public function __call($methodName , $arguments){
        switch(count($arguments)){
            case 0 :
                return 0;
            case 1 :
                return $arguments[0] * self::pi;
            case 2 :
                return $arguments[0] * $arguments[1] * self::pi;
        }
    }
}


$overObj = new Overload();

echo $overObj->area().   "\n"; // returns 0
echo $overObj->area(1) . "\n"; // returns 3.141432
echo $overObj->area(1,2)."\n"; // returns 6.282864

?>