func main() {
	for i := 0; i < 10; i++ {
		//開啟并發(fā)打印
		go func(i int) {
			fmt.Printf("hello goroutine : %d \n", i)
		}(i)
	}
	time.Sleep(time.Millisecond)
}

func main() {
	var a [10]int
	for i := 0; i < 10; i++ {
		//如果這里不將i傳入?yún)?shù)直接引用外部的參數(shù)會(huì)出現(xiàn)：數(shù)據(jù)沖突（race condition）
		go func(i int) {
			// 打印語句會(huì)進(jìn)行協(xié)程的調(diào)度，會(huì)交出控制權(quán)：fmt.Printf("hello goroutine : %d \n", i)
			a[i]++
			//通過 Gosched() 可以手動(dòng)交出協(xié)程的控制權(quán)；如果不寫這個(gè)語句協(xié)程就不會(huì)交出控制權(quán)進(jìn)行調(diào)度執(zhí)行，就會(huì)一直卡死在這里
			runtime.Gosched()
		}(i)
	}
	time.Sleep(time.Millisecond)
	fmt.Println(a)
}

func chanDemo() {
	//var c chan int //為 nil 的chan不能使用
	c := make(chan int)
    go func() {
		for  {
			n := <- c
			fmt.Println(n)
		}
	}()
    c <- 1 //向 c 里面發(fā)送數(shù)據(jù)（在發(fā)送時(shí)需要 goroutine 來進(jìn)行接收，否則就會(huì)死鎖）
    c <- 2
}

func worker(i int, c chan int) {
	for  {
		fmt.Printf("Worker :%d, accpet: %c \n", i, <-c)
	}
}
func chanDemo() {
	var channels [10]chan int
	for i := 0; i < 10; i++ {
		channels[i] = make(chan int)
		go worker(i, channels[i])
	}
	for i := 0; i < 10; i++ {
		channels[i] <- 'a' + i
	}
	for i := 0; i < 10; i++ {
		channels[i] <- 'A' + i
	}
}

// chan<- int :代表只能發(fā)數(shù)據(jù)； <-chan int:代表只能收數(shù)據(jù)
func worker(i int) chan int {
	c := make(chan int)
	go func() {
		for  {
			fmt.Printf("Worker :%d, accpet: %c \n", i, <-c)
		}
	}()
	return c
}
func chanDemo() {
	var channels [10]chan int
	for i := 0; i < 10; i++ {
		channels[i] = worker(i) 
	}
	for i := 0; i < 10; i++ {
		channels[i] <- 'a' + i
	}
	for i := 0; i < 10; i++ {
		channels[i] <- 'A' + i
	}
}

func chanClose() {
	//創(chuàng)建一個(gè)緩沖區(qū)
	c := make(chan int, 3)
	c <- 1
	c <- 2
	c <- 3
	//方法一：
	go func() {
		for  {
			//如果沒有接收到數(shù)據(jù)就直接返回
			if i, ok := <-c; !ok {
				fmt.Println(" close channel.....")
				break
			} else {
				//死循環(huán)讀取，如果外部 chan 已經(jīng)關(guān)閉了，這里會(huì)一直接收具體數(shù)據(jù)的默認(rèn)值
				fmt.Printf("%d\n", i)
			}
		}
	}()
    //方法二：
    go func() {
		for n := range c {
			//如果沒有接收到數(shù)據(jù)就直接返回
			fmt.Printf("%d\n", n)
		}
	}()
	//close關(guān)閉 channel
	close(c)
}

func ChanDemo() {
	workers := make([]worker, 10)
	for i, _ := range workers {
		workers[i] = createWorker(i)
	}
	for i, worker := range workers{
		worker.in <- 'a' + i
	}
	for i, worker := range workers{
		worker.in <- 'A' + i
	}
	//這種方式可以接收消費(fèi)者傳入的數(shù)據(jù)，如果消費(fèi)者傳入的數(shù)據(jù)是同步的話，這里也會(huì)出現(xiàn)死鎖
	for _, worker := range workers {
		<- worker.done
		<- worker.done
	}
}
//定義一個(gè)worker的結(jié)構(gòu)用來存放 chan數(shù)據(jù)
type worker struct {
	done chan bool
	in chan int
}
func createWorker(id int) worker  {
	w := worker{
		done: make(chan bool),
		in: make(chan int),
	}
	go doWorker(id, w.in, w.done)
	return w
}
func doWorker(id int, in chan int, done chan bool)  {
	for i := range in {
		fmt.Printf("Worker:%d, accept:%c \n", id, i)
		go func() {
			//異步發(fā)送，否則會(huì)出現(xiàn)死鎖，因?yàn)榘l(fā)送會(huì)加鎖
			done <- true
		}()
	}
}

//定義一個(gè)worker的結(jié)構(gòu)用來存放 chan數(shù)據(jù)
type done2Worker struct {
	in chan int
	//使用指針傳遞
	wg *sync.WaitGroup
}
func create2Worker(id int, group *sync.WaitGroup) done2Worker  {
	w := done2Worker{
		wg: group,
		in: make(chan int),
	}
	go do2Worker(id, w)
	return w
}
func do2Worker(id int, worker2 done2Worker)  {
	for i := range worker2.in {
		fmt.Printf("Worker:%d, accept:%c \n", id, i)
		//執(zhí)行完成
		worker2.wg.Done()
	}
}
func Chan2Demo() {
	var wg sync.WaitGroup
	workers := make([]done2Worker, 10)
	for i, _ := range workers {
		workers[i] = create2Worker(i, &wg)
	}
	wg.Add(20)
	for i, worker := range workers {
		worker.in <- 'a' + i
	}
	for i, worker := range workers {
		worker.in <- 'A' + i
	}
	wg.Wait()
}

func generator() chan int {
	out := make(chan int)
	go func() {
		i := 0
		for {
			//休眠隨機(jī)數(shù)
			time.Sleep(time.Duration(rand.Intn(1500)) * time.Millisecond)
			out <- i
			i++
		}
	}()
	return out
}
func main() {
	//非阻塞式獲取數(shù)據(jù)，誰先出數(shù)據(jù)就執(zhí)行哪一段邏輯
	var c1, c2 = generator(), generator()
	// 10秒鐘后發(fā)送一次數(shù)據(jù)
	after := time.After(time.Second * 10)
	//每秒鐘都會(huì)寫一次數(shù)據(jù)
	tick := time.Tick(time.Second)
	//死循環(huán)獲取channel中的數(shù)據(jù)
	for  {
		select {
		//會(huì)通過select關(guān)鍵字進(jìn)行調(diào)用，誰先來數(shù)據(jù)，就執(zhí)行誰
		case n := <-c1:
			fmt.Println("Received from c1:", n)
		case n := <-c2:
			fmt.Println("Received from c2:", n)
		case <-after:
			fmt.Println("ten second after......")
		case <-tick:
			fmt.Println("tick task exec .....")
		default:
			fmt.Println("No value received")
		}
	}
}

type atomicInt struct {
	a int
    //定義互斥量進(jìn)行同步
	lock sync.Mutex
}
func (a *atomicInt) add()  {
	a.lock.Lock()
	defer a.lock.Unlock()
	a.a++
}
func main() {
	a := atomicInt{
		a: 0,
	}
	a.add()
	go a.add()
	time.Sleep(time.Millisecond)
	fmt.Println("value : ", a.a)
}

//傳入多個(gè)chan，返回一個(gè)只能輸出的chan
func fanIn(chs...chan string) <-chan string {
	//創(chuàng)建管道
	c := make(chan string)
    //這里循環(huán)讀取 chs 管道傳入的數(shù)據(jù)
	for _ , ch := range chs {
		go func(in chan string) {
			for  {
				//循環(huán)從chCopy里面讀取數(shù)據(jù)后傳入到返回出去的chan
                //這里不能直接使用 ch ，因?yàn)樵撟兞渴且粋€(gè)閉包，后續(xù)遍歷的管道會(huì)將其覆蓋
				c <- <-in
			}
		}(ch)
	}
	return c
}
//創(chuàng)建一個(gè)channel，循環(huán)的發(fā)送數(shù)據(jù)
func msgGen(serviceName string) chan string {
	ch := make(chan string)
	go func() {
		for  {
			ch<- fmt.Sprintf("hello：%s", serviceName)
		}
	}()
	return ch
}
func main() {
	s1 := msgGen("service1")
	s2 := msgGen("service2")
	s3 := msgGen("service3")
	//可以拿到返回出來的 channel 跟服務(wù)繼續(xù)做交互
	m := fanIn(s1, s2, s3)
	for  {
		fmt.Println(<-m)
	}
}

// ChannelCreateFunc 創(chuàng)建接口，需要傳入管道，以及參數(shù)
type ChannelCreateFunc interface {
	// Create 創(chuàng)建函數(shù)傳入一個(gè)任何類型的管道，后面參數(shù)選擇性傳入
	Create(ch <-chan any, V...any) (any, bool)
}
func Creator(c ChannelCreateFunc, ch <-chan any) {
	if r, ok := c.Create(ch, time.Duration(time.Second)); ok {
		fmt.Println(r)
	} else {
		fmt.Println("未接收到數(shù)據(jù)")
	}
}
func main() {
	s1 := msgGen("service1")
	m := fanIn(s1)
	Creator(timeout.TimeoutCreator{}, m)
	Creator(noblock.NotBlockCreator{}, m)
}

type NotBlockCreator struct {
}
func (n NotBlockCreator) Create(ch <-chan any, V...any) (any, bool) {
	select {
	case m := <-ch:
		return m, true
	default:
		return "", false
	}
}

type TimeoutCreator struct {
}
func (t TimeoutCreator) Create(ch <-chan any, V...any) (any, bool) {
	size := len(V)
	if size == 1 {
		var timeoutValue = V[0]
		switch v := timeoutValue.(type) {
		case time.Duration:
			for  {
				select {
				case m := <-ch:
					return m, true
				case <-time.After(v):
					fmt.Println("數(shù)據(jù)超時(shí)接收，直接返回false")
					return "", false
				}
			}
		}
	}
	return "", false
}

// Fscanf函數(shù)在讀取文件時(shí)，遇到\r為默認(rèn)替換為0，讀取\n結(jié)束，如果編碼不對(duì)，這里讀取就會(huì)出問題
func readMaze(path string) [][]int {
	file, err := os.Open(path)
	if err != nil {
		panic(err)
	}
	var row, col int
	//這里需要取地址，函數(shù)里面會(huì)更改row和col的值
	fmt.Fscanf(file, "%d %d", &row, &col)
	fmt.Printf("%d\t%d\n", row, col)
	//創(chuàng)建一個(gè)二位數(shù)組，一共有多少行
	maze := make([][]int, row)
	for i := range maze {
		//創(chuàng)建列
		maze[i] = make([]int, col)
		for j := range maze[i] {
			fmt.Fscanf(file, "%d", &maze[i][j])
		}
	}
	return maze
}
func main() {
	//讀取迷宮文件
	maze := readMaze("maze/maze.in")
	for _, row := range maze {
		for _, col := range row {
			fmt.Printf("%d\t", col)
		}
		fmt.Println()
	}
}

//點(diǎn)位的結(jié)構(gòu)體
type point struct {
	i, j int
}
//定義需要探索的方向
var dirs = [4]point {
	//當(dāng)前位置-1，就是向上
	{-1, 0},
	//左邊的點(diǎn)位
	{0, -1},
	//向下的點(diǎn)位
	{1, 0},
	//向右的點(diǎn)位
	{0, 1},
}
//將兩個(gè)點(diǎn)位相加，就可以獲取到下一個(gè)點(diǎn)位
func (p point) add(r point) point {
	return point{p.i + r.i, p.j + r.j}
}
func (p point) at(grid [][]int) (int, bool) {
	//首先判斷點(diǎn)位是否越界了，例如傳入的點(diǎn)位 (-1,0)或者(1, -1)
	if p.i < 0 || p.i >= len(grid) {
		return 0, false
	}
	//判斷j列是否越界了
	if p.j < 0 || p.j >= len(grid[p.i]) {
		return 0, false
	}
	//返回?cái)?shù)據(jù)
	return grid[p.i][p.j], true
}
// walk 傳入迷宮，指定迷宮開始的點(diǎn)位，以及出口的點(diǎn)位
func walk(maze [][]int, start, end point) [][]int  {
	//創(chuàng)建走過的步
	steps := make([][]int, len(maze))
	for i := range steps {
		steps[i] = make([]int, len(maze[i]))
	}
	//創(chuàng)建需要探索的隊(duì)列，初始的點(diǎn)位(0,0)
	Q := []point{start}
	for len(Q) > 0 {
		cur := Q[0]
		//截取出隊(duì)列中的頭部
		Q = Q[1:]
		//判斷如果點(diǎn)位等于出口的點(diǎn)位，那么直接退出
		if cur == end {
			break
		}
		//dirs為點(diǎn)位周邊的四個(gè)方向，我這里采用的是 上、左、下、右 的方向進(jìn)行探索
		for _, dir := range dirs {
			//將當(dāng)前點(diǎn)位跟四個(gè)方向相加，例如 (0,0) 向上的方向就是(-1,0)，將i的值進(jìn)行減1
			next := cur.add(dir)
			//判斷向上的點(diǎn)位不能超出迷宮的界限，并且返回在迷宮中的值，因?yàn)槿绻祷氐闹禐?，就證明是墻
			val, ok := next.at(maze)
			if !ok || val == 1 {
				continue
			}
			//不等0就證明是墻
			val, ok = next.at(steps)
			if !ok || val != 0 {
				continue
			}
			//如果是起點(diǎn)，就跳過
			if next == start {
				continue
			}
			//獲取到當(dāng)前步數(shù)的值
			curSteps, _ := cur.at(steps)
			//將走過的點(diǎn)位追加到切片中
			steps[next.i][next.j] = curSteps + 1
			//繼續(xù)將下一個(gè)點(diǎn)位添加到需要探索的隊(duì)列當(dāng)中
			Q = append(Q, next)
		}
	}
	return steps
}