# gmp_scan0

(PHP 4 >= 4.0.4, PHP 5)

gmp_scan0 — Scan for 0

### Description

int gmp_scan0 ( resource `$a` , int `$start` )

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

### Parameters

`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.

### Return Values

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

### Examples

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";
?>`

The above example will output:

    3
    7