<?php

// your code goes here
$formula = '[Spaledar] $v0 $v1 - $v2';
$vars = ["v0"=>"Connected","v1"=>"Viet Name","v2"=>"Hebus jifo"];

echo "\n $formula";
			
$replaced = preg_replace_callback("/\$(v\d+)/", function ($tokens) use ($vars){
		echo "\n".$tokens[1];
		return $vars[$tokens[1]];
	}, $formula);
echo "\n $replaced";