Go_Concurrency_Patterns_2012/16_daisyChain.go at master · drgrib/Go_Concurrency_Patterns_2012 · GitHub

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package main

import (
	"fmt"
	"math/rand"
	"time"
)

//////////////////////////////////////////////
/// aliases
//////////////////////////////////////////////

var println = fmt.Println
var sprintf = fmt.Sprintf
var printf = fmt.Printf

//////////////////////////////////////////////
/// init
//////////////////////////////////////////////

func init() {
	s := time.Now().UTC().UnixNano()
	rand.Seed(s)
}

//////////////////////////////////////////////
/// functions
//////////////////////////////////////////////

func f(left, right chan int) {
	left <- 1 + <-right
}

func main() {
	const n = 100000
	leftmost := make(chan int)
	right := leftmost
	left := leftmost
	for i := 0; i < n; i++ {
		right = make(chan int)
		go f(left, right)
		left = right
	}
	go func(c chan int) { c <- 1 }(right)
	println(<-leftmost)
}