func RunScenario1() {
    count := 10
    var wg sync.WaitGroup

    for i := 0; i < count; i++ {
       wg.Add(1)
       go func(index int) {
           defer wg.Done()
           doSomething(index)
       }(i)
    }

    wg.Wait()
}

func RunScenario2() {
  timeout := time.Now().Add(time.Second * time.Duration(10))
  n := runtime.NumCPU()

  waitForAll := make(chan struct{})
  done := make(chan struct{})
  concurrentCount := make(chan struct{}, n)

  for i := 0; i < n; i++ {
    concurrentCount <- struct{}{}
  }

  go func() {
    for time.Now().Before(timeout) {
      <-done
      concurrentCount <- struct{}{}
    }

    waitForAll <- struct{}{}
  }()

  go func() {
    for {
      <-concurrentCount
      go func() {
        doSomething(rand.Intn(n))
        done <- struct{}{}
      }()
    }
  }()

  <-waitForAll
}

func RunScenario3() {
    numOfConcurrency := runtime.NumCPU()
    taskTool := 10
    jobs := make(chan int, taskTool)
    results := make(chan int, taskTool)
    var wg sync.WaitGroup

    // workExample
    workExampleFunc := func(id int, jobs <-chan int, results chan<- int, wg *sync.WaitGroup) {
       defer wg.Done()
       for job := range jobs {
           res := job * 2
           fmt.Printf("Worker %d do things, produce result %d \n", id, res)
           time.Sleep(time.Millisecond * time.Duration(100))
           results <- res
       }
    }

    for i := 0; i < numOfConcurrency; i++ {
       wg.Add(1)
       go workExampleFunc(i, jobs, results, &wg)
    }

    totalTasks := 100 // 本例就要从文件列表里读取

    wg.Add(1)
    go func() {
       defer wg.Done()
       for i := 0; i < totalTasks; i++ {
           n := <-results
           fmt.Printf("Got results %d \n", n)
       }
       close(results)
    }()

    for i := 0; i < totalTasks; i++ {
       jobs <- i
    }
    close(jobs)
    wg.Wait()
}

func RunScenario4() {
    sth := make(chan string)
    result := make(chan string)
    go func() {
       id := rand.Intn(100)
       for {
           sth <- doSomething(id)
       }
    }()
    go func() {
       for {
           result <- takeSomthing(<-sth)
       }
    }()

    select {
    case c := <-result:
       fmt.Printf("Got result %s ", c)
    case <-time.After(time.Duration(30 * time.Second)):
       fmt.Errorf("指定时间内都没有得到结果")
    }
}

func RunScenario5() {
  concurrencyCount := runtime.NumCPU()
  for i := 0; i < concurrencyCount; i++ {
    go func(index int) {
      for {
        doUploadMock()
      }
    }(i)
  }

  t := time.NewTicker(time.Second)
  for {
    select {
    case <-t.C:
      // 计算并打印实时数据
    }
  } 
}