func main() { c := make(chan int, 1000) for i := 0; i < 100; i++ { go foo(c) } sum := 0 for r := range c { sum += r } fmt.Println(sum) } func foo(c chan int) { r := rand.Int() for i := 0; i < r; i++ { c <- r } } --- func main() { c := make(chan int, 1000) var wg sync.WaitGroup wg.Add(100) for i := 0; i < 100; i++ { go func() { defer wg.Done() foo(c) }() } go func() { wg.Wait() close(c) }() sum := 0 for r := range c { sum += r } // // fmt.Println(sum) } func foo(c chan int) { r := rand.Int() for i := 0; i < r; i++ { c <- r } }

Birinchi kod variantida muammo bor: for r := range c sikli cheksiz kutadi, chunki c kanali hech qachon yopilmaydi. Shu sababli, dastur to'xtab qoladi.

Ikkinchi variantda, barcha gorutinlarning yakunlanishini kutish uchun sync.WaitGroup qo'shilgan va undan so'ng c kanali yopilgan. Bu, kanal o'qish siklidan to'g'ri chiqishni ta'minlaydi.

Asosiy nuqtalar:

• Barcha gorutinlarning yakunlanishini kuzatish uchun sync.WaitGroup ishlatiladi.
• Barcha yozuvlar tugagach, kanal yopiladi.
• for r := range c sikli, kanal yopilganda tugaydi.

Tuzatilgan kod misoli:

group := sync.WaitGroup{}
group.Add(100)
for i := 0; i < 100; i++ {
    go func() {
        defer group.Done()
        foo(c)
    }()
}
go func() {
    group.Wait()
    close(c)
}()

sum := 0
for r := range c {
    sum += r
}