prior

About prior

prior is a priority queue based on golang container/heap.

Explation

Node: node is the unit insert to queue. Node has attributes:
Key: key associated with node, can be nil
value: value of key, can be nil
Priority:priority of node
Index: index in queue

API

Push(Node) : push a node into queue, O(logN) where N is queue length
Pop(Node) : fetch node with max priority, O(1)
Remove(index): remove a specified node of index, O(logN) where N is queue length
Length() : queue length

Example

package main

import (
    "fmt"
    "time"
    "github.com/insionng/prior"
)

func main() {
    pq := prior.NewPriorityQueue()
    //写入队列
    type Meta struct {
        Timestamp int64
        Symbol    string
        Price     float64
        Quantity  float64
        Source    string
    }
    var meta Meta
    for i := 0; i < 100; i++ {
        meta.Timestamp = time.Now().Unix()
        meta.Symbol = "glod:usd"
        meta.Price = 1000.8 + float64(i)
        meta.Quantity = 0.8 + float64(i)
        if i%2==0 {
            meta.Source = "en"
        } else {
            meta.Source = "zh"
        }

        //pq.Push(prior.NewNode(nil, meta, meta.Price*-1))
        pq.AddNode(nil, meta, meta.Price*-1)
    }

    //读取队列
    for pq.Length() > 0 {
        v := pq.Pop()
        if v == nil {
            break
        }
        if value, okay := v.GetValue().(Meta); okay {
            fmt.Println(value)
        }
    }
}