What are some examples of priority queue implementations?

What are some examples of priority queue implementations?

Priority queues can be implemented using various data structures like heaps, linked lists, or arrays. Would you like to see code examples?

Yes, please provide a code example using a binary heap.

Here's a simple implementation of a priority queue using a binary heap in Python:

class PriorityQueue:
    def __init__(self):
        self.heap = []

    def push(self, item, priority):
        heapq.heappush(self.heap, (priority, item))

    def pop(self):
        return heapq.heappop(self.heap)[1]

pq = PriorityQueue()
pq.push('task1', 1)
pq.push('task2', 5)
pq.push('task3', 3)
print(pq.pop())  # Outputs: task1

What about using a linked list for a priority queue?

In a linked list implementation, you can insert elements in order based on their priority. Here's a simple example:

class Node:
    def __init__(self, data, priority):
        self.data = data
        self.priority = priority
        self.next = None

class LinkedList:
    def __init__(self):
        self.head = None

    def insert(self, data, priority):
        new_node = Node(data, priority)
        if not self.head or self.head.priority > priority:
            new_node.next = self.head
            self.head = new_node
        else:
            current = self.head
            while current.next and current.next.priority <= priority:
                current = current.next
            new_node.next = current.next
            current.next = new_node

    def pop(self):
        if self.head:
            data = self.head.data
            self.head = self.head.next
            return data
        return None