3v4l.org

run code in 500+ PHP versions simultaneously
<?php $sample = array('a.col1','a.col2','b.col1','c.col1','c.col2','d.col5'); foreach ($sample as $column) { ${strstr($column, '.', true)}[] = $column; } var_export($a); var_export($b); var_export($c); var_export($d);

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48.22 ms | 1510 KiB | 5 Q