package main

import (

	"fmt"

	"math/rand"

	"runtime"

	"sync"

	"sync/atomic"

	"time"

)

func main() {

	var state = make(map[int]int)

	var mutex = &sync.Mutex{}

	var ops int64 = 0

	for r := 0; r < 100; r++ {

		//起100个协程

		go func() {

			total := 0

			for {

				key := rand.Intn(5)

				//读取map中的数据加锁

				mutex.Lock()

				total += state[key]

				mutex.Unlock()

				atomic.AddInt64(&ops, 1)

				runtime.Gosched()

			}

		}()

	}

	for w := 0; w < 10; w++ {

		go func() {

			for {

				key := rand.Intn(5)

				val := rand.Intn(100)

				//写入map中的数据加锁

				mutex.Lock()

				state[key] = val

				mutex.Unlock()

				atomic.AddInt64(&ops, 1)

				runtime.Gosched()

			}

		}()

	}

	time.Sleep(time.Second)

	opsFinal := atomic.LoadInt64(&ops)

	fmt.Println("ops:", opsFinal)

	//加锁读取state的数据

	mutex.Lock()

	fmt.Println("state:", state)

	mutex.Unlock()

}