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gmp_com

(PHP 4 >= 4.0.4, PHP 5)

gmp_com — Calculates one's complement

说明

resource gmp_com ( resource $a )

Returns the one's complement of a.

参数

a: 可以是一个 GMP 数据 resouce，或一个可以转换为数值的字符串。

返回值

Returns the one's complement of a, as a GMP number.

范例

Example #1 gmp_com() example


<?php
$com = gmp_com("1234");
echo gmp_strval($com) . "\n";
?>

以上例程会输出：

-1235

在线手册：中文英文

PHP手册 - N: Calculates one's complement

用户评论:

xo at jdbartlett dot com (14-Apr-2010 06:07)

If you're using one's compliment (bitwise NOT) to flip all $a's bits, don't forget that you need to use a mask to specify how many bits you expect in your result: <?php gmp_and(gmp_com('1234'), '2047') ?> >> 813 // 01100101101 in binary I chose 2047 because 1234 is an 11-bit binary number and 2047 is the maximum an 11-bit register can hold: 11111111111 (2047) 10011010010 (1234) 01100101101 (813)