golang does not repeat queue

During the development process, queue is a very practical data structure. When using queues, you may encounter some problems, such as how to implement no repeat queue.

In many scenarios, we need to add elements to the queue, but if the element already exists in the queue, we need to ignore it to avoid adding duplicate elements. At this time, we need to use a non-duplicate queue.

In Golang, we can use map to implement non-duplicate queues. Specifically, we can put elements into a map as keys, and the values ​​can be set to true or any other value. If the key already exists in the map, we can ignore it. Otherwise, we can add the element to the queue.

The following is a sample code that uses map to implement a non-duplicate queue:

type uniqueQueue struct {
    items map[string]bool
    queue []string
}

func newUniqueQueue() *uniqueQueue {
    return &uniqueQueue{
        items: make(map[string]bool),
        queue: []string{},
    }
}

func (q *uniqueQueue) enqueue(item string) {
    if !q.items[item] {
        q.items[item] = true
        q.queue = append(q.queue, item)
    }
}

func (q *uniqueQueue) dequeue() string {
    item := q.queue[0]
    q.queue = q.queue[1:]
    delete(q.items, item)
    return item
}

func (q *uniqueQueue) isEmpty() bool {
    return len(q.queue) == 0
}

In the above code, we define a type called uniqueQueue, which contains A map of items and an array of queue. items is used to save the elements that already exist in the queue, and queue is used to save the order of elements in the queue.

We implement the function of adding elements to the queue in the enqueue method. When adding an element, we first need to determine whether the element exists in items. If it does not exist, we can add the element to queue and set the corresponding value of the element in items to true. Otherwise, we need to ignore the element.

In the dequeue method, we implement the function of removing elements from the queue. Specifically, we remove the first element from the queue and delete the element from items. Finally, we return the removed element.

In the isEmpty method, we determine whether the queue is empty. This method returns true if there are no elements in the queue.

Using the above code, we can easily implement non-duplicate queues and avoid the appearance of duplicate elements, thus improving the efficiency and performance of the code.

The above is the detailed content of golang does not repeat queue. For more information, please follow other related articles on the PHP Chinese website!