3v4l.org

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<?php $arrCombined = array(); $arrColors = array('R', 'B', 'G' ,'Y'); $arrNumbers = array('1', '2', '3', '4'); foreach($arrColors as $colorK => $colorV) { echo $colorV.' => '.$arrNumbers[$colorK]; echo "\n"; }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
R => 1 B => 2 G => 3 Y => 4

preferences:
218.34 ms | 405 KiB | 338 Q