<?php

if (isset($_POST['knopka'])) {

    echo $_POST['name'];

    if (isset($_POST['name']) && isset($_POST['second_name']) && isset($_POST['email'])) {
        if (isset($_POST['CPU']) && isset($_POST['GPU'])) {
            if (isset($_POST['OZU']) && isset($_POST['PZU'])) {
                if (isset($_POST['check_one']) && isset($_POST['check_two'])) {

                    $name = $_POST['name'];
                    $second_name = $_POST['second_name'];
                    $email = $_POST['email'];
                    $CPU = $_POST['CPU'];
                    $GPU = $_POST['GPU'];
                    $OZU = $_POST['OZU'];
                    $PZU = $_POST['PZU'];

                    $name = htmlspecialchars($name);
                    $second_name = htmlspecialchars($second_name);
                    $email = htmlspecialchars($email);
                    $CPU = htmlspecialchars($CPU);
                    $GPU = htmlspecialchars($GPU);
                    $OZU = htmlspecialchars($OZU);
                    $PZU = htmlspecialchars($PZU);

                    $name = urldecode($name);
                    $second_name = urldecode($second_name);
                    $email = urldecode($email);
                    $CPU = urldecode($CPU);
                    $GPU = urldecode($GPU);
                    $OZU = urldecode($OZU);
                    $PZU = urldecode($PZU);

                    $name = trim($name);
                    $second_name = trim($second_name);
                    $email = trim($email);
                    $CPU = trim($CPU);
                    $GPU = trim($GPU);
                    $OZU = trim($OZU);
                    $PZU = trim($PZU);

                    echo $name;

                } else {
                    echo "Check check!";
                }

            } else {
                echo "Write size \"OZU\" and \"PZU\"";
            }
        } else {
            echo "Write model of  \"CPU\" and \"GPU\"";
        }
    } else {
        echo "<center><p><b> Write your name and second name </b></p></center>";
    }

}