jqueue

golang resizable queue implementation

Usage

Create a queue

// create a resizable queue with
// starting capacity of 10
q = NewRingQueue(10, true)

// create a fixed size queue with
// capacity of 20
q = NewRingQueue(20, false)

Resize a queue

The queue will automatically resize when trying to enque if the queue is full. The resize function takes 1 argument, factor, which is the factor to expand the queue by. If you attempt to Enqueue when the queue is full, the automatic resize will grow the queue by 1.25, or 25%

Ex:

// doubles the queue size
q.ResizeQueue(2)

// grows queue by 25%
// note: this is the default behavior
q.ResizeQueue(1.25)

// shrinks the queue to 75% of current size
q.ResizeQueue(0.75)

// resize before enqueue
if q.isFull {
  q.Resize(2)
  q.Enqueue(data)
}

Note: Queue capacity is always an int value, so value of capacity will round down to nearest whole number

Get element(s)

// pop a single element
element, isEmpty := q.Dequeue()

// pop 5 elements
elements, isEmpty := q.DequeueAmount(5)

Example implementation

func main() {
    rq := jqueue.NewRingQueue(5, true)

    rq.Enqueue(1)
    rq.Enqueue(2)
    rq.Enqueue(3)
    rq.Enqueue(4)
    rq.Enqueue(5)

    dequeued, empty := rq.DequeueAmount(3)
    fmt.Println("Dequeued:", dequeued, "Empty:", empty) // Output: Dequeued: [1 2 3] Empty: false

    rq.Enqueue(6)
    dequeued, isEmpty = rq.DequeueAmount(4)
    fmt.Println("Dequeued:", dequeued, "Empty:", empty) // Output: Dequeued: [4 5 6] Empty: true

    dequeued, isEmpty = rq.DequeueAmount(5)
    fmt.Println("Dequeued:", dequeued, "Empty:", empty) // Output: Dequeued: [] Empty: true

    rq.Print() // Output: Queue elements: Queue is empty
}