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<?php |
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<?php |
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// +----------------------------------------------------------------------+ |
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// +----------------------------------------------------------------------+ |
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// | PHP Version 4 | |
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// | PHP Version 4 | |
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// +----------------------------------------------------------------------+ |
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// +----------------------------------------------------------------------+ |
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// | Copyright (c) 1997-2004 The PHP Group | |
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// | Copyright (c) 1997-2004 The PHP Group | |
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// +----------------------------------------------------------------------+ |
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// +----------------------------------------------------------------------+ |
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// | This source file is subject to version 3.0 of the PHP license, | |
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// | This source file is subject to version 3.0 of the PHP license, | |
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// | that is bundled with this package in the file LICENSE, and is | |
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// | that is bundled with this package in the file LICENSE, and is | |
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// | available at through the world-wide-web at | |
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// | available at through the world-wide-web at | |
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// | http://www.php.net/license/3_0.txt. | |
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// | http://www.php.net/license/3_0.txt. | |
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// | If you did not receive a copy of the PHP license and are unable to | |
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// | If you did not receive a copy of the PHP license and are unable to | |
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// | obtain it through the world-wide-web, please send a note to | |
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// | obtain it through the world-wide-web, please send a note to | |
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// | license@php.net so we can mail you a copy immediately. | |
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// | license@php.net so we can mail you a copy immediately. | |
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// +----------------------------------------------------------------------+ |
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// +----------------------------------------------------------------------+ |
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// | Authors: Aidan Lister <aidan@php.net> | |
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// | Authors: Aidan Lister <aidan@php.net> | |
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// +----------------------------------------------------------------------+ |
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// +----------------------------------------------------------------------+ |
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// |
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// |
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// $Id: bcpowmod.php,v 1.2 2005/11/22 20:24:45 aidan Exp $ |
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// $Id: bcpowmod.php,v 1.2 2005/11/22 20:24:45 aidan Exp $ |
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|
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/** |
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/** |
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* Replace bcpowmod() |
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* Replace bcpowmod() |
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* |
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* |
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* @category PHP |
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* @category PHP |
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* @package PHP_Compat |
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* @package PHP_Compat |
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* @link http://php.net/function.bcpowmod |
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* @link http://php.net/function.bcpowmod |
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* @author Sara Golemon <pollita@php.net> |
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* @author Sara Golemon <pollita@php.net> |
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* @version $Revision: 1.2 $ |
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* @version $Revision: 1.2 $ |
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* @since PHP 5.0.0 |
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* @since PHP 5.0.0 |
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* @require PHP 4.0.0 (user_error) |
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* @require PHP 4.0.0 (user_error) |
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*/ |
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*/ |
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if (!function_exists('bcpowmod')) { |
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if (!function_exists('bcpowmod')) { |
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function bcpowmod($x, $y, $modulus, $scale) |
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function bcpowmod($x, $y, $modulus, $scale) |
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{ |
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{ |
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// Sanity check |
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// Sanity check |
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if (!is_scalar($x)) { |
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if (!is_scalar($x)) { |
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user_error('bcpowmod() expects parameter 1 to be string, ' . |
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user_error('bcpowmod() expects parameter 1 to be string, ' . |
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gettype($x) . ' given', E_USER_WARNING); |
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gettype($x) . ' given', E_USER_WARNING); |
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return false; |
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return false; |
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} |
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} |
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|
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|
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if (!is_scalar($y)) { |
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if (!is_scalar($y)) { |
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user_error('bcpowmod() expects parameter 2 to be string, ' . |
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user_error('bcpowmod() expects parameter 2 to be string, ' . |
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gettype($y) . ' given', E_USER_WARNING); |
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gettype($y) . ' given', E_USER_WARNING); |
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return false; |
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return false; |
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} |
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} |
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|
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|
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if (!is_scalar($modulus)) { |
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if (!is_scalar($modulus)) { |
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user_error('bcpowmod() expects parameter 3 to be string, ' . |
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user_error('bcpowmod() expects parameter 3 to be string, ' . |
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gettype($modulus) . ' given', E_USER_WARNING); |
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gettype($modulus) . ' given', E_USER_WARNING); |
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return false; |
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return false; |
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} |
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} |
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|
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|
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if (!is_scalar($scale)) { |
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if (!is_scalar($scale)) { |
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user_error('bcpowmod() expects parameter 4 to be integer, ' . |
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user_error('bcpowmod() expects parameter 4 to be integer, ' . |
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gettype($scale) . ' given', E_USER_WARNING); |
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gettype($scale) . ' given', E_USER_WARNING); |
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return false; |
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return false; |
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} |
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} |
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|
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|
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$t = '1'; |
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$t = '1'; |
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while (bccomp($y, '0')) { |
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while (bccomp($y, '0')) { |
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if (bccomp(bcmod($y, '2'), '0')) { |
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if (bccomp(bcmod($y, '2'), '0')) { |
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$t = bcmod(bcmul($t, $x), $modulus); |
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$t = bcmod(bcmul($t, $x), $modulus); |
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$y = bcsub($y, '1'); |
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$y = bcsub($y, '1'); |
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} |
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} |
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|
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|
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$x = bcmod(bcmul($x, $x), $modulus); |
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$x = bcmod(bcmul($x, $x), $modulus); |
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$y = bcdiv($y, '2'); |
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$y = bcdiv($y, '2'); |
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} |
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} |
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|
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return $t; |
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return $t; |
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} |
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} |
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} |
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} |
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|
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|
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?> |
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?> |
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