- substr_replace: documentation ( source)
- implode: documentation ( source)
- range: documentation ( source)
<?php
namespace WebSharks\Challenge;
$a = ['patdumona', 'kristinedp', 'raamdes', 'renzmp', 'reedysete'];
$r = range('D','Z',3);
echo implode(substr_replace($a,$r +=4 ,-1))."\n";