Objective : Implement a priority queueExtra Credits: Solve the starvation problem using any simple, suitable technique1) Write a queue class using linked list to implement the queue. Do not us the link list from STL. The queue class should be a template class and must implement enqueue and dequeue operations. It should also have a getQLength() function that returns the number of elements in the queue.2) Write a PriQueue class that uses the queue class. The PriQueue is also a template class. It should take a parameter levels as input to specify the number of priority levels. The constructor should create a vector pq of size levels to create the various priority levels. pq should be a private variable. It should overload the enqueue operation from Queue class: void enqueue(T obj, int level). It allows you to specify the priority level of the object obj so that you can place the object in the right queue. By default, the enqueue operation puts the object in queue 0 (lowest priority). Therefore, the function void enqueue(T obj) should place the object in queue pq[0]. The dequeue operation needs to check the queues in the order of priority. The higher levels need to be served before the lower ones. As long as there is something in the higher queue, the lower queue cannot be served. (Note that there are other ways to implement priority but we are sticking to this rule).3) The PriQueue should implement a function void increaseLevel() that adds another priority level by inserting another level in the vector pq. For example:Queue q;pq.pushback(q).4) Test your implementation using a driver program. You should try enqueuing and dequeuing at various levels and submit the ouput along wth the code.5) Please explain each syntax line with comments.6) Do not copy the codes from online!