gmp_scan1

(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)

gmp_scan1Scan for 1

Description

gmp_scan1(GMP|int|string $num1, int $start): int

Scans num1, starting with bit start, towards more significant bits, until the first set bit is found.

Parameters

num1

The number to scan.

A GMP object, an int or a numeric string.

start

The starting bit.

Return Values

Returns the index of the found bit, as an int. If no set bit is found, -1 is returned.

Examples

Example #1 gmp_scan1() example

<?php
// "1" bit is found at position 3. index starts at 0
$s1 gmp_init("01000"2);
echo 
gmp_scan1($s10) . "\n";

// "1" bit is found at position 9. index starts at 5
$s2 gmp_init("01000001111"2);
echo 
gmp_scan1($s25) . "\n";
?>

The above example will output:

3
9