PHP5中文手册·Scan for 0 -- 追寻梦想＞编程乐园＞PHP 编程

说明

int gmp_scan0 ( resource $a , int $start )

Scans a , starting with bit start , towards more significant bits, until the first clear bit is found.

参数

a

The number to scan.

It can be either a GMP number resource, or a numeric string given that it is possible to convert the latter to a number.

start

The starting bit.

返回值

Returns the index of the found bit, as an integer. The index starts from 0.

范例

Example#1 gmp_scan0() example


<?php
// "0" bit is found at position 3. index starts at 0
$s1 = gmp_init("10111", 2);
echo gmp_scan0($s1, 0) . "\n";

// "0" bit is found at position 7. index starts at 5
$s2 = gmp_init("101110000", 2);
echo gmp_scan0($s2, 5) . "\n";
?>

上例将输出：

3
7


	PHP5中文手册 gmp_random gmp_scan1 GMP PHP Manual gmp_scan0 (PHP 4 >= 4.0.4, PHP 5) gmp_scan0 — Scan for 0 说明 int gmp_scan0 ( resource `$a` , int `$start` ) Scans `a` , starting with bit `start` , towards more significant bits, until the first clear bit is found. 参数 `a` The number to scan. It can be either a GMP number resource, or a numeric string given that it is possible to convert the latter to a number. `start` The starting bit. 返回值 Returns the index of the found bit, as an integer. The index starts from 0. 范例 Example#1 gmp_scan0() example `<?php // "0" bit is found at position 3. index starts at 0 $s1 = gmp_init("10111", 2); echo gmp_scan0($s1, 0) . "\n"; // "0" bit is found at position 7. index starts at 5 $s2 = gmp_init("101110000", 2); echo gmp_scan0($s2, 5) . "\n"; ?>` 上例将输出： 3 7 gmp_random gmp_scan1 GMP PHP Manual