3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = [ '1.1', '1.2', '1.3', '2.1', '2.2', '2.3', '3.1', '3.2', ]; $result = []; foreach ($array as $v) { sscanf($v, '%d', $major); if (!isset($ref[$major])) { $result[] = &$ref[$major]; } $ref[$major][] = $v; } var_export($result);

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40.07 ms | 402 KiB | 5 Q