<?php
    function check4dup1($string, $array, $delimiter = ","){
        $skills = '';
        $temparr = explode($delimiter, $string);
        foreach($temparr as $str){
            if(in_array($str, $array)){
                $skills .= "${str}, ";
            }
        }
        $skills = substr($skills, 0, strlen($skills) - 2);
        return 'SKILLS: '.$skills;
    }
    function check4dup2($string, $array, $delimiter = ","){
        $temparr = explode($delimiter, $string);
        $arrSkills = array_intersect($temparr, $array);
        return 'SKILLS: ' . implode(", ", $arrSkills);
    }
 
    $string = "illustration,drawing,printing,coding,programming";
    
    $array = Array (
	    0 => "illustration",
	    1 => "drawing",
	    2 => "painting",
	    3 => "ceramics",
	    4 => "sports",
	    5 => "programming"
	);
 
	echo(check4dup1($string, $array).PHP_EOL);
	echo(check4dup2($string, $array).PHP_EOL);
	
	?>