How to add elements to a heap in Go?

In Go, you can add elements to a heap structure using the container/heap package. To do this, follow these steps:

Create a custom struct to represent your heap elements. This struct must implement the heap.Interface interface which consists of three methods: Len(), Swap(), and Less(). These methods define the behavior of the heap.

type Item struct {
    value    interface{}
    priority int
    // Add any other fields you need
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int {
    return len(pq)
}

func (pq PriorityQueue) Swap(i, j int) {
    pq[i], pq[j] = pq[j], pq[i]
}

func (pq PriorityQueue) Less(i, j int) bool {
    return pq[i].priority < pq[j].priority
}

// Implement the Push and Pop methods for the heap.Interface

func (pq *PriorityQueue) Push(x interface{}) {
    item := x.(*Item)
    *pq = append(*pq, item)
}

func (pq *PriorityQueue) Pop() interface{} {
    old := *pq
    n := len(old)
    item := old[n-1]
    *pq = old[0 : n-1]
    return item
}

Create an instance of the PriorityQueue structure.

pq := &PriorityQueue{}

Add elements to the heap by pushing new items onto the PriorityQueue using the Push() method.

item1 := &Item{value: "A", priority: 3}
item2 := &Item{value: "B", priority: 1}
item3 := &Item{value: "C", priority: 2}

heap.Push(pq, item1)
heap.Push(pq, item2)
heap.Push(pq, item3)

Here, we are adding three items to the heap with different priorities.

That's it! You have successfully added elements to a heap in Go using the container/heap package. You can now continue to use the heap's functionality, such as removing the minimum element or updating element priorities.