JS Data Structures: Queues, see more at: https://medium.com/p/17f714057817

DATA_STRUCTURES_priorityQueueUsingJSNativeFunctions.js

function PriorityQueue() {
  let priority = []
  let nonPriority = []

  class PublicPriorityQueue {
    size() {
      return priority.length + nonPriority.length
    }

    isEmpty() {
      return this.size() === 0
    }

    enqueue(data, isPriority = 0) {
      const element = isPriority === 1 ? priority : nonPriority
      element.push(data)
    }

    dequeue() {
      const element = priority.length > 0 ? priority : nonPriority
      return element.shift()
    }

    peek() {
      const element = priority.length > 0 ? priority : nonPriority
      return element[0]
    }

    print() {
      return [...priority, ...nonPriority].toString()
    }
  }

  return new PublicPriorityQueue()
}