golang面试题-顺序打印cat、dog、fish各100次

package main

import (
	"fmt"
	"sync"
)


func PrintCat(fishCH,catCH chan bool){
	defer waitgroup.Done()
	defer close(catCH)
	for i:= 0; i <100;i++{
		<-fishCH
		fmt.Println("cat ...")
		catCH <- true
	}
}

func PrintDog(catCH,dogCH chan bool){
	defer waitgroup.Done()
	defer close(dogCH)
	for i:= 0; i <100;i++{
		<-catCH
		fmt.Println("dog ...")
		dogCH<-true
	}
}

func PrintFish(dogCH,fishCH chan bool){
	defer waitgroup.Done()
	defer close(fishCH)
	for i:= 0; i <100;i++{
		<-dogCH
		fmt.Println("fish ...")
		fishCH<-true
	}
}


var waitgroup sync.WaitGroup

func main() {

	catCH := make(chan bool,1)
	dogCH := make(chan bool,1)
	fishCH := make(chan bool,1)
	fishCH <- true


	go PrintFish(dogCH,fishCH)
	go PrintDog(catCH,dogCH)
	go PrintCat(fishCH,catCH)

	waitgroup.Add(3)
	waitgroup.Wait()

}