Question

How to implement queue in Node.js

Answer 1

class Queue {
    constructor() {
        this.items = [];
    }
    
    enqueue(element) {
        return this.items.push(element);
    }
    
    dequeue() {
        if (this.items.length > 0) {
            return this.items.shift();
        }
    }
    
    size() {
        return this.items.length;
    }

    
    peek() {
        return this.items[this.items.length - 1];
    }
    
    isEmpty() {
       return this.items.length == 0;
    }
   
    print() {
        for (let i = 0; i < this.items.length; i++) {
          	console.log(this.items[i]);
      	}
    }
 
    delete(){
        this.items = [];
    }
}

let queue = new Queue();

queue.enqueue(6);
queue.enqueue(8);
queue.enqueue(2);
queue.enqueue(3);
queue.enqueue(0);
queue.enqueue(1);

console.log(queue.items);

queue.dequeue();
console.log(queue.items);

console.log(queue.peek());

console.log(queue.isEmpty());

console.log("size: " + queue.size());

queue.dequeue();
queue.print();

queue.delete();
console.log(queue.items);





/*
run:

[ 6, 8, 2, 3, 0, 1 ]
[ 8, 2, 3, 0, 1 ]
1
false
size: 5
2
3
0
1
[]

*/

 

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