基于3个goroutine交替顺序打印自然数

Myth丶恋晨 2022-12-06 04:12 162阅读 0赞

筚路蓝缕，以启山林。抚有蛮夷，以属华夏。不鸣则已，一鸣惊人。  
                                                                                                              ——《左传\`宣公十二年》

**今儿看到了一个题目，电脑开着顺手实现下。方便起见，下文以A、B、C字母来标识三个goroutine。这个题目方式还是很多的，代码变换多样。上代码：**

姿势1：chan通知与切换

一句话来描述思路：A对B说：我搞完了，轮到你了，B对C说：我搞完了，轮到你了，C对A说：我搞完了，轮到你了......子子孙孙无穷匮也、

func main() {
    	chA, chB, chC := make(chan string), make(chan string), make(chan string)
    
    	go func() {
    		for i := 1; ; {
    			select {
    			case <-chA:
    				fmt.Println("[A]:", i)
    				chB <- "B"
    				i += 3
    			}
    		}
    	}()
    
    	go func() {
    		for i := 2; ; {
    			select {
    			case <-chB:
    				fmt.Println("[B]:", i)
    				chC <- "C"
    				i += 3
    			}
    		}
    	}()
    
    	go func() {
    		for i := 3; ; {
    			if i == 3 {
    				chA <- "A"
    			}
    			select {
    			case <-chC:
    				fmt.Println("[C]:", i)
    				chA <- "A"
    				i += 3
    			}
    		}
    	}()
    
    	for !false {
    		fmt.Print()
    	}
    }
    
    
    控制台：
    [A]: 1
    [B]: 2
    [C]: 3
    [A]: 4
    [B]: 5
    [C]: 6
    [A]: 7
    [B]: 8
    [C]: 9
    [A]: 10
    [B]: 11
    [C]: 12
    [A]: 13
    [B]: 14
    [C]: 15
    [A]: 16
    [B]: 17
    [C]: 18
    [A]: 19
    [B]: 20
    [C]: 21
    [A]: 22
    [B]: 23
    [C]: 24
    ...
    ...
    ...

姿势2：换一下角色，打印操作交给main线，写入由A、B、C各自完成

type Data struct { //便捷起见，将数字和要打印它的goroutine标识进行绑定
    	Name string
    	Num  int
    }
    
    func main() {
    	chA, chB, chC := make(chan Data), make(chan Data), make(chan Data)
    	go func() {
    		for i := 1; ; {
    			var data0 = Data{Name: "A", Num: i}
    			chA <- data0
    			i += 3
    		}
    	}()
    	go func() {
    		for i := 2; ; {
    			var data0 = Data{Name: "B", Num: i}
    			chB <- data0
    			i += 3
    		}
    	}()
    	go func() {
    		for i := 3; ; {
    			var data0 = Data{Name: "C", Num: i}
    			chC <- data0
    			i += 3
    		}
    	}()
    
    	flag := false
    	for !flag {
    		dataA := <-chA
    		fmt.Println("["+dataA.Name+"]:", dataA.Num)
    		dataB := <-chB
    		fmt.Println("["+dataB.Name+"]:", dataB.Num)
    		dataC := <-chC
    		fmt.Println("["+dataC.Name+"]:", dataC.Num)
    	}
    }
    
    控制台：
    [A]: 1
    [B]: 2
    [C]: 3
    [A]: 4
    [B]: 5
    [C]: 6
    [A]: 7
    [B]: 8
    [C]: 9
    [A]: 10
    [B]: 11
    [C]: 12
    [A]: 13
    [B]: 14
    [C]: 15
    [A]: 16
    [B]: 17
    [C]: 18
    [A]: 19
    [B]: 20
    [C]: 21
    [A]: 22
    [B]: 23
    [C]: 24
    ...
    ...
    ...

姿势3：就以打印结果来衡量的话，sleep也能用上

type Obj struct {
    	Name string
    	Num  int
    }
    
    func main() {
    	objCh := make(chan Obj)
    	go func() {
    		for !false {
    			select {
    			case data := <-objCh:
    				fmt.Println("["+data.Name+"]:", data.Num)
    			}
    		}
    	}()
    	go func() {
    		for !false {
    			select {
    			case data := <-objCh:
    				fmt.Println("["+data.Name+"]:", data.Num)
    
    			}
    		}
    	}()
    	go func() {
    		for !false {
    			select {
    			case data := <-objCh:
    				fmt.Println("["+data.Name+"]:", data.Num)
    			}
    		}
    
    	}()
    
    	for i := 1; ; i++ {
    		obj := Obj{Num: i}
    		if (i-1)%3 == 0 {
    			obj.Name = "A"
    			objCh <- obj
    			time.Sleep(time.Second * 1)
    			continue
    		}
    		if (i-2)%3 == 0 {
    			obj.Name = "B"
    			objCh <- obj
    			time.Sleep(time.Second * 1)
    			continue
    		}
    		if (i-3)%3 == 0 {
    			obj.Name = "C"
    			objCh <- obj
    			time.Sleep(time.Second * 1)
    			continue
    		}
    	}
    }
    
    
    控制台：
    [A]: 1
    [B]: 2
    [C]: 3
    [A]: 4
    [B]: 5
    [C]: 6
    [A]: 7
    [B]: 8
    [C]: 9
    [A]: 10
    [B]: 11
    [C]: 12
    [A]: 13
    [B]: 14
    [C]: 15
    [A]: 16
    [B]: 17
    [C]: 18
    [A]: 19
    [B]: 20
    [C]: 21
    [A]: 22
    [B]: 23
    [C]: 24
    ...
    ...
    ...

方式很多，欢迎各位看官一起交流，喜欢可以留个赞哦！

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[go_redis]: https://lan6193.blog.csdn.net/article/details/108938119
[go_redis 1]: https://lan6193.blog.csdn.net/article/details/108931188
[go_goroutine]: https://lan6193.blog.csdn.net/article/details/105715373
[go]: https://lan6193.blog.csdn.net/article/details/108670428
[go_goroutine 1]: https://lan6193.blog.csdn.net/article/details/105559568
[go_go_channel_goroutine]: https://lan6193.blog.csdn.net/article/details/97528721
[go_channel]: https://lan6193.blog.csdn.net/article/details/101201408
[go_WaitGroup]: https://lan6193.blog.csdn.net/article/details/100887891
[channel]: https://lan6193.blog.csdn.net/article/details/97656420
[go_B_A_B_A]: https://lan6193.blog.csdn.net/article/details/108901339
[go 1]: https://lan6193.blog.csdn.net/article/details/103298105