structure_old/priority_queue/priority_queue.go

115 lines
2.1 KiB
Go

package plist
import (
"github.com/davecgh/go-spew/spew"
"github.com/emirpasic/gods/utils"
)
// PriorityQueue 优先队列 适合数据量不大, 加索引
type PriorityQueue struct {
data []interface{}
left, right, mid int
cap int
size int
isSorted bool
comparator utils.Comparator
}
// NewWithInt compare use int
func NewWithInt() *PriorityQueue {
p := new(PriorityQueue)
p.cap = 11
p.mid = 5
p.data = make([]interface{}, p.cap, p.cap)
p.comparator = func(a, b interface{}) int {
if a.(int) > b.(int) {
return 1
}
return -1
}
return p
}
func (pq *PriorityQueue) String() string {
return "(" + spew.Sprint(pq.data[pq.mid]) + "," + spew.Sprint(pq.size) + ")" + spew.Sprint(pq.Values())
}
func (pq *PriorityQueue) reMakeData() {
var temp []interface{}
if pq.cap <= 1024 {
pq.cap = pq.cap*2 + 1
temp = make([]interface{}, pq.cap, pq.cap)
} else {
pq.cap = pq.cap*5/8*2 + 1
temp = make([]interface{}, pq.cap, pq.cap)
}
pq.mid = (pq.cap - 1) / 2
left := pq.mid - pq.size/2
copy(temp[left:], pq.data[pq.left:pq.right])
pq.left = left
pq.right = pq.left + pq.size
pq.data = temp
}
func (pq *PriorityQueue) Push(v interface{}) {
if pq.size == 0 {
pq.data[pq.mid] = v
pq.left = pq.mid
pq.right = pq.mid + 1
pq.size = 1
return
}
midvalue := pq.data[pq.mid]
if pq.comparator(v, midvalue) > 0 {
if pq.left == 0 {
pq.reMakeData()
}
pq.left--
pq.data[pq.left] = v
} else {
if pq.right == pq.cap {
pq.reMakeData()
}
pq.data[pq.right] = v
pq.right++
}
pq.isSorted = false
pq.size++
}
// 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.data[pq.left:pq.right]
if !pq.isSorted {
utils.Sort(values, pq.comparator)
pq.isSorted = true
}
return values
}