<?php
echo preg_replace('/.*(\d+)(x|xE)(\d+).*/', 'D$1xF$3', 'Toster2x04Questions'); echo PHP_EOL, PHP_EOL;
echo preg_replace('/.*(\d+)(x|xE)(\d+).*/', 'D$1xF$3', 'TosterS2xE04Questions');
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