Implementing Stacks & Queues

Why does this Queue implementation use an object instead of an array?

class Queue {
  constructor() {
    this.front = 0;
    this.rear = 0;
    this.items = {};
  }
  
  enqueue(element) {
    this.items[this.rear] = element;
    this.rear++;
  }
  
  dequeue() {
    if (this.isEmpty()) return null;
    const element = this.items[this.front];
    delete this.items[this.front];
    this.front++;
    return element;
  }
}

Objects are faster than arrays
To support larger queue sizes
To optimize memory usage in dequeue
Using an object optimizes memory because: 1) Avoids array shift operations in dequeue which are O(n), 2) Enables efficient deletion of front elements without restructuring, 3) Maintains constant time O(1) for enqueue and dequeue operations, 4) Reduces memory reallocation overhead, 5) Better handles large numbers of operations, 6) Allows sparse storage with numeric keys, 7) Improves performance for high-throughput scenarios, 8) Common optimization in production queue implementations.
To enable random access

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