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<?php function createStringFromMap($map) { $chars = array('C*'); end($map); $last = key($map); for ($i = $j = $char = 0; $i <= $last; $i++) { $bit = isset($map[$i]) ? $map[$i] : 0; $char |= ($bit << (7 - $j)); if (++$j === 8) { $chars[] = $char; $j = $char = 0; } } return call_user_func_array('pack', $chars); } $map = array(); $map[1] = 1; $map[9] = 1; $map[17] = 1; $map[25] = 1; echo createStringFromMap($map);
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, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
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297.1 ms | 406 KiB | 460 Q