<?php
 
error_reporting(-1);
 
$telephone = "+7 -(911)-506-5656 ";
$regexp = '/^(8|\\+\\s?7)([\\s*\\-*\\(*]*)[0-9]{3}(([\\s*\\-*\\)*\\(*]*)[0-9]){7}([\\s*\\-*\\)*\\(*]*)$/';
 
if (preg_match($regexp, $telephone)) {
	echo "Номер введён верно, азаза!\n";
} else {
	echo "Пожалуйста, введите номер из 11 цифр, начинающийся с 8 или +7!\n";
}
$regexpPlusSeven = '/\\+\\s?7/';
$withoutPlusSeven = preg_replace($regexpPlusSeven, '8', $telephone);
$regexpClean = '/(\\s|\\-|\\(|\\))/';
$result = preg_replace($regexpClean, '', $withoutPlusSeven);
	echo "Набранный номер: $result\n";
 
?>

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