Developer
<?php
namespace Faker\Provider\pt_BR;
/**
* Calculates one MOD 11 check digit based on customary Brazilian algorithms.
*
* @see http://en.wikipedia.org/wiki/Check_digit
* @see http://pt.wikipedia.org/wiki/CNPJ#Algoritmo_de_Valida.C3.A7.C3.A3o
* @see http://en.wikipedia.org/wiki/Cadastro_de_Pessoas_F%C3%ADsicas#Validation
*
* @param int|string $numbers Numbers on which generate the check digit
*
* @return int
*/
function check_digit($numbers)
{
$numbers = (string) $numbers;
$length = strlen($numbers);
$second_algorithm = $length >= 12;
$verifier = 0;
for ($i = 1; $i <= $length; ++$i) {
if (!$second_algorithm) {
$multiplier = $i + 1;
} else {
$multiplier = ($i >= 9) ? $i - 7 : $i + 1;
}
$verifier += $numbers[$length - $i] * $multiplier;
}
$verifier = 11 - ($verifier % 11);
if ($verifier >= 10) {
$verifier = 0;
}
return $verifier;
}
Developer
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