3v4l.org

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<?php $array = [ 'list[P] = 1', 'list[A] = 1', 'list[F] = 2', 'list[B] = 1' ]; array_multisort( preg_replace('#\D+#', '', $array), SORT_ASC, SORT_NUMERIC, array_keys($array), $array ); var_export($array);

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