Snippet for medium post

concurrent_factorial.go

package main

import "fmt"

// Factorial recursive function to find the factorial result
// using go routines and the channel passed as parameter
func Factorial(number int, product int, ch chan int) {
	// Calculate the product until this point
	product = product * number

	// If the number if one we are done and the factorial is finished
	if number == 1 {
		// Send through the channel the factorial result
		ch <- product
		// Stop the execution since we found what we were looking for
		return
	}

	// Recursive call for the next value sendig the new number and
	// the current value of the product
	go Factorial(number-1, product, ch)
}

func main() {
	ch := make(chan int)
	number := 5

	// First call to Factorial recursive function
	go Factorial(number, 1, ch)
	// Read from the channel when the value is already computed
	answer := <-ch

	fmt.Printf("%d!= %d\n", number, answer)
}