<?php
/**
* A simple array-backed queue, based off of the classic Okasaki
* persistent amortized queue. The basic idea is to maintain two
* stacks: an input stack and an output stack. When the output
* stack runs out, reverse the input stack and use it as the output
* stack.
*
* We don't use the SPL implementation because it's only supported
* on PHP 5.3 and later.
*
* Exercise: Prove that push/pop on this queue take amortized O(1) time.
*
* Exercise: Extend this queue to be a deque, while preserving amortized
* O(1) time. Some care must be taken on rebalancing to avoid quadratic
* behaviour caused by repeatedly shuffling data from the input stack
* to the output stack and back.
*/
class HTMLPurifier_Queue {
private $input;
private $output;
public function __construct($input = array()) {
$this->input = $input;
$this->output = array();
}
/**
* Shifts an element off the front of the queue.
*/
public function shift() {
if (empty($this->output)) {
$this->output = array_reverse($this->input);
$this->input = array();
}
if (empty($this->output)) {
return NULL;
}
return array_pop($this->output);
}
/**
* Pushes an element onto the front of the queue.
*/
public function push($x) {
array_push($this->input, $x);
}
/**
* Checks if it's empty.
*/
public function isEmpty() {
return empty($this->input) && empty($this->output);
}
}
About Section
NFC Pay was founded with a vision to transform the way people handle transactions. Our journey is defined by a commitment to innovation, security, and convenience. We strive to deliver seamless, user-friendly payment solutions that make everyday transactions effortless and secure. Our mission is to empower you to pay with ease and confidence, anytime, anywhere.
FAQ Section
Here are answers to some common questions about NFC Pay. We aim to provide clear and concise information to help you understand how our platform works and how it can benefit you. If you have any further inquiries, please don’t hesitate to contact our support team.
Download the app and sign up using your email or phone number, then complete the verification process.
Yes, we use advanced encryption and security protocols to protect your payment details.
Absolutely, you can link multiple debit or credit cards to your wallet.
Go to the transfer section, select the recipient, enter the amount, and authorize the transfer.
Use the “Forgot PIN” feature in the app to reset it following the provided instructions.
Sign up for a merchant account through the app and follow the setup instructions to start accepting payments.
Yes, you can view and track your payment status in the account dashboard