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.
可以是一个 GMP 数据 resouce，或一个可以转换为数值的字符串。
- 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 以上例程会输出：
<?php
// "0" bit is found at position 3. index starts at 0
$s1 = gmp_init("10111", 2);
echo gmp_scan0($s1, 0) . "
";
// "0" bit is found at position 7. index starts at 5
$s2 = gmp_init("101110000", 2);
echo gmp_scan0($s2, 5) . "
";
?>
3
7
