Online PHP editor | output for rdO0q

<?php $arr = ['Format 10x10', 'Format 20x20', 'Format 100x100']; print "strnatcasecmp:\n"; usort($arr, 'strnatcasecmp'); var_dump($arr); print "\n\nstrcasecmp:\n"; usort($arr, 'strcasecmp'); var_dump($arr); print "\n\nCollator:\n"; $collator = new Collator('en'); // 2. Use usort with the collator's compare method usort($arr, [$collator, 'compare']); var_dump($arr); print "\n\nCollator (with numeric):\n"; $collator->setAttribute(Collator::NUMERIC_COLLATION, Collator::ON); // 2. Use usort with the collator's compare method usort($arr, [$collator, 'compare']); var_dump($arr);