A simple implementation of the Priority Queue data structure in JavaScript. This repository demonstrates how to create a priority queue class with essential methods and explains its functionality with practical examples.
A Priority Queue is a data structure that stores elements in a way that allows efficient access to the element with the highest priority. Each element in the queue is assigned a priority value, and elements with higher priority are dequeued before elements with lower priority. Priority queues are commonly implemented using heaps.
- Enqueue: Add an element to the queue with a given priority.
- Dequeue: Remove and return the element with the highest priority.
- Peek: View the element with the highest priority without removing it.
- isEmpty: Check if the queue is empty.
- Size: Get the number of elements in the queue.
Here’s the JavaScript implementation of the priority queue:
class PriorityQueue { constructor() { this.queue = []; } // Add an element to the queue with a given priority enqueue(element, priority) { const item = { element, priority }; if (this.isEmpty()) { this.queue.push(item); } else { let added = false; for (let i = 0; i < this.queue.length; i++) { if (item.priority > this.queue[i].priority) { this.queue.splice(i, 0, item); added = true; break; } } if (!added) { this.queue.push(item); } } } // Remove and return the element with the highest priority dequeue() { if (this.isEmpty()) { return "Queue is empty!"; } return this.queue.shift(); } // View the element with the highest priority without removing it peek() { if (this.isEmpty()) { return "Queue is empty!"; } return this.queue[0]; } // Check if the queue is empty isEmpty() { return this.queue.length === 0; } // Get the size of the queue size() { return this.queue.length; } }
// Initialize the priority queue const pq = new PriorityQueue(); // Enqueue elements with priorities pq.enqueue("Task 1", 1); pq.enqueue("Task 2", 3); pq.enqueue("Task 3", 2); // Peek at the highest priority element console.log(pq.peek()); // Output: { element: 'Task 2', priority: 3 } // Dequeue elements console.log(pq.dequeue()); // Output: { element: 'Task 2', priority: 3 } console.log(pq.dequeue()); // Output: { element: 'Task 3', priority: 2 } // Check if the queue is empty console.log(pq.isEmpty()); // Output: false // Get the size of the queue console.log(pq.size()); // Output: 1
- Task Scheduling: Managing tasks based on priority in operating systems.
- Dijkstra's Algorithm: Finding the shortest path in graphs.
- Job Scheduling: For scheduling jobs with different priorities in computers.
- Bandwidth Management: Prioritizing network traffic based on importance.
Want to see a quick tutorial on how to build this? Check out this TikTok video:
- Clone the repository:
git clone https://github.com/fix2015/structure_priority_queue cd structure_priority_queue - Open the file
index.jsin your favorite code editor. - Run the file using Node.js:
node index.js
Contributions are welcome! If you have suggestions or want to add new features, feel free to create a pull request.
This project is licensed under the MIT License.
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