public function testEverything()
{
$queue = new Queue();
$this->assertTrue($queue->is_empty());
$queue->push_back(1);
$queue->push_back(2);
$queue->push_back(3);
$this->assertFalse($queue->is_empty());
$this->assertEquals(1, $queue->pop_front());
$this->assertEquals(2, $queue->pop_front());
$this->assertEquals(3, $queue->pop_front());
$this->assertTrue($queue->is_empty());
$queue->push_back(4);
$this->assertFalse($queue->is_empty());
$this->assertEquals(4, $queue->pop_front());
$in_cnt = 0;
$out_cnt = 0;
for ($i = 1; $i < 50; $i++) {
for ($j = 0; $j < $i; $j++) {
$queue->push_back($in_cnt);
$in_cnt++;
}
$this->assertEquals($out_cnt, $queue->pop_front());
$out_cnt++;
}
while (!$queue->is_empty()) {
$this->assertEquals($out_cnt, $queue->pop_front());
$out_cnt++;
}
}
*/
public function enqueue($el)
{
array_push($this->_queue, $el);
}
/**
* Dequeue the front element from the queue.
*
* @return mixed $element.
*/
public function dequeue()
{
if ($this->front() !== null) {
return array_shift($this->_queue);
}
return null;
}
}
// Example usage:
$queue = new Queue();
$queue->enqueue("Element");
$queue->enqueue(23);
$queue->enqueue(array(3, 4, 6));
while (!$queue->is_empty()) {
echo "The front element is now : \n";
var_dump($queue->front());
echo "\n";
$queue->dequeue();
}
// Outputs NULL
var_dump($queue->front());
