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run code in 150+ php & hhvm versions
Bugs & Features
<?php $wordlist = array('testing','testing','testing','testing','testing','testing','testing','testing','testing','testing','testing','testing'); for($i = 0; $i == count($wordlist); $i++){ $concatenated .= $wordlist[i]; } echo $concatenated;
Output for 5.0.4 - 7.1.0
Notice: Undefined variable: concatenated in /in/GW6F3 on line 7
Output for 4.3.0 - 5.0.3
Notice: Undefined variable: concatenated in /in/GW6F3 on line 7