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run code in 300+ PHP versions simultaneously
<?php $re = '/\b(\d+(?:\.\d+)?)mcg\b/'; $str = 'some text 0.25mcg some more text some text 25mcg some more text'; preg_match_all($re, $str, $matches); print_r($matches[1]);

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24.18 ms | 402 KiB | 5 Q