respect-validation/library/Rules/PrimeNumber.php
Alexandre Gomes Gaigalas ab3732f91f Use SPDX IDs for licensing
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adhere better to FOSS standards. It is also machine-readable.
2023-02-19 00:19:10 -03:00

49 lines
1 KiB
PHP

<?php
/*
* Copyright (c) Alexandre Gomes Gaigalas <alganet@gmail.com>
* SPDX-License-Identifier: MIT
*/
declare(strict_types=1);
namespace Respect\Validation\Rules;
use function ceil;
use function is_numeric;
use function sqrt;
/**
* Validates whether the input is a prime number.
*
* @author Alexandre Gomes Gaigalas <alganet@gmail.com>
* @author Camilo Teixeira de Melo <kmilotxm@gmail.com>
* @author Henrique Moody <henriquemoody@gmail.com>
* @author Ismael Elias <ismael.esq@hotmail.com>
* @author Kleber Hamada Sato <kleberhs007@yahoo.com>
*/
final class PrimeNumber extends AbstractRule
{
/**
* {@inheritDoc}
*/
public function validate($input): bool
{
if (!is_numeric($input) || $input <= 1) {
return false;
}
if ($input != 2 && ($input % 2) == 0) {
return false;
}
for ($i = 3; $i <= ceil(sqrt((float) $input)); $i += 2) {
if ($input % $i == 0) {
return false;
}
}
return true;
}
}