PHP Manual
后退前进

gmp_setbit

(PHP 4 >= 4.0.4, PHP 5)

gmp_setbit -- Set bit

Description

void gmp_setbit ( resource &a, int index [, bool set_clear])

Sets bit index in a. set_clear defines if the bit is set to 0 or 1. By default the bit is set to 1. Index starts at 0.

注: Unlike most of the other GMP functions, gmp_setbit() must be called with a GMP resource that already exists (using gmp_init() for example). One will not be automatically created.

例子 1. gmp_setbit() example

<?php
$a = gmp_init("0xfd");
gmp_setbit($a, 1); // index starts at 0
echo gmp_strval($a) . "\n";
?>

The printout of the above program will be: 

255

See also gmp_clrbit().

后退起点前进
gmp_scan1上一级gmp_sign