gmp_scan1

Description

int gmp_scan1 ( resource a, int start)

Scans a, starting with bit start, towards more significant bits, until the first set bit is found. Returns the index of the found bit. If no set bit is found, -1 is returned.

例子 1. gmp_scan1() example


<?php
// "1" bit is found at position 3. index starts at 0
$s1 = gmp_init("01000", 2);
echo gmp_scan1($s1, 0) . "\n";

// "1" bit is found at position 9. index starts at 5
$s2 = gmp_init("01000001111", 2);
echo gmp_scan1($s2, 5) . "\n";
?>

The printout of the above program will be:

3
9