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<?php // convert decimal to base 2 without using base_convert $base = 2; $num = 23; while( $num > 0) { $arr[] = $num % $base; // store remainder in array $num = floor($num/$base); // no integer division } var_dump($arr); $cat = join('',$arr); var_dump($cat);
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 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(5) { [0]=> int(1) [1]=> int(1) [2]=> int(1) [3]=> int(0) [4]=> int(1) } string(5) "11101"
preferences:
213.72 ms | 406 KiB | 315 Q