Go use goroutines to print 1~10

main.go

package main

func printN(n int, prev <-chan struct{}, next chan<- struct{}) {
	<-prev // wait for the previous signal
	println(n)
	next <- struct{}{} // activate the next goroutine
}

func printAll(n int) {
	if n < 1 {
		return
	}

	channels := make([]chan struct{}, n)
	for i := range channels {
		channels[i] = make(chan struct{})
	}

	for i := 1; i <= n; i++ {
		prev := channels[i-1]
		next := channels[i%n]

		go printN(i, prev, next)
	}

	channels[0] <- struct{}{} // send the start signal
	<-channels[0]             // wait for the finishing signal
}

func main() {
	// use goroutines to print 1~10
	printAll(10)
}