structure_old/priority_queue/priority_queue.go

package plist

import (
	"log"

	"github.com/emirpasic/gods/utils"
)

// PriorityQueue 优先队列 适合数据量不大, 加索引
type PriorityQueue struct {
	left, right, mid int
	datas            []interface{}
	size             int
	comparator       utils.Comparator
	isSorted         bool
}

// NewWithInt compare use int
func NewWithInt() *PriorityQueue {
	p := new(PriorityQueue)
	p.datas = make([]interface{}, 8)
	p.comparator = func(a, b interface{}) int {
		if a.(int) > b.(int) {
			return 1
		}
		return -1
	}
	return p
}

func (pq *PriorityQueue) reArrange() {

}

func (pq *PriorityQueue) reMakeMemory() {

	var incSize int
	if pq.size >= 1048 {
		incSize = pq.size / 2
	} else {
		incSize = pq.size
	}

	capacity := pq.size + incSize
	temp := make([]interface{}, capacity)

	mid := capacity / 2
	left := mid - pq.size/2 - 1

	x := pq.datas
	copy(temp[left+1:], pq.datas[pq.left+1:pq.right])
	pq.datas = temp
	pq.left = left
	pq.mid = mid
	pq.right = pq.size + pq.left

	log.Println(x, pq.datas, pq.left, pq.right)

}

func (pq *PriorityQueue) search(v interface{}) int {
	// left := pq.left
	// right := pq.right

	data := pq.datas[pq.left+1 : pq.right]
	left := 0
	mid := 0
	right := len(data)

	for left < right-1 {
		mid = (left + right) / 2 // 4 10 7 10 8 10 9 10 | 4 10 4 7 4 5
		if pq.comparator(v, data[mid]) > 0 {
			left = mid
		} else {
			right = mid
		}
	}

	if pq.comparator(v, data[left]) > 0 {
		return left + 1
	} else {
		return left
	}
}

func (pq *PriorityQueue) Push(v interface{}) {

	defer func() {
		if err := recover(); err != nil {

			log.Println(pq.datas)
			log.Println(pq.left, pq.right, pq.size)
			log.Panic(err)

		}
	}()

	if pq.size == 0 {

		pq.mid = len(pq.datas) / 2
		pq.left = pq.mid - 1
		pq.right = pq.mid + 1

		pq.datas[pq.mid] = v

		log.Println(pq.datas)
		log.Println(pq.left)

	} else {

		// if pq.comparator(v, pq.datas[pq.mid]) > 0 {

		// 	if pq.right >= len(pq.datas) {
		// 		// 重建 datas
		// 		pq.reMakeMemory()
		// 	}

		// 	pq.datas[pq.right] = v
		// 	pq.right++

		// } else {

		// 	if pq.left-1 < 0 {
		// 		// 重建 datas
		// 		pq.reMakeMemory()
		// 	}
		// 	pq.left--
		// 	pq.datas[pq.left] = v
		// }

		idx := pq.search(v)
		log.Println("idx:", idx)
		if idx > pq.size/2 {

			if pq.right >= len(pq.datas) {
				pq.reMakeMemory()
			}

			offset := pq.left + 1 + idx
			copy(pq.datas[offset+1:], pq.datas[offset:pq.right])
			pq.datas[offset] = v
			pq.right++
			// log.Println("right: ", pq.datas)

		} else {

			if pq.left < 0 {
				// 重建 datas
				pq.reMakeMemory()
			}

			offset := pq.left + 1 + idx
			copy(pq.datas[pq.left:], pq.datas[pq.left+1:offset])
			pq.datas[offset] = v
			pq.left--

			// log.Println("left: ", pq.datas)
		}

	}

	pq.size++
	log.Println("push:", pq.datas)
	// if pq.isSorted {
	// 	pq.isSorted = false
	// }
}

// func (pq *PriorityQueue) PopTop() (interface{}, bool) {

// 	return v, isok
// }

// func (pq *PriorityQueue) PopBottom() (interface{}, bool) {

// 	return v, isok
// }

func (pq *PriorityQueue) Top() (interface{}, bool) {
	return pq.Get(0)
}

func (pq *PriorityQueue) Bottom() (interface{}, bool) {
	return pq.Get(pq.right - 1)
}

func (pq *PriorityQueue) Get(index int) (interface{}, bool) {
	if index < pq.size {
		return pq.Values()[index], true
	}
	return nil, false
}

func (pq *PriorityQueue) Values() []interface{} {
	// values := pq.datas[pq.left:pq.right]
	// if !pq.isSorted {
	// 	utils.Sort(values, pq.comparator)
	// 	pq.isSorted = true
	// }
	return pq.datas[pq.left:pq.right]
}