gmp_scan0

Scan for 0 (PHP 4 >= 4.0.4, PHP 5)
int gmp_scan0 ( resource a, int start )

Scans a, starting with bit start, towards more significant bits, until the first clear bit is found. Returns the index of the found bit. The index starts from 0.

例 691. 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";
?>

The printout of the above program will be:

3
7