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  • gmp_com()

    (PHP 4 >= 4.0.4, PHP 5, PHP 7)

    Calculates one's complement

    说明

    gmp_com(GMP$a): GMP

    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

    gmp_com() example

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

    以上例程会输出:

    -1235
    
    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)

    上篇:gmp_cmp()

    下篇:gmp_div_q()