Golang practicing code

goroutines.go

package main

import (
	"fmt"
	"time"
)

var (
      done = make(chan bool)
      i int = 0
	)

func say(s string, n int) {
	for i := 0; i < n; i++ {
		time.Sleep(100 * time.Millisecond)
		fmt.Println(s)
	}
}

func wrapSays(s string, n int){
	i ++
	go func(){say(s,n); done <- true}()		
}

func Done(){
	for j := 0 ; j < i ; j++ {<- done;}; fmt.Print("DONE!!!")
}

func main() {
	defer Done()
	wrapSays("a", 4)
	wrapSays("b", 5)
	wrapSays("d", 5)
}

select.go

package main

import "fmt"

func fibonacci(c, quit chan int) {
	x, y := 0, 1
	for { // infinit loop until 'quit' channel to be updated
		select {
		  case c <- x: // each time that request <-c this case will be executed
			   x, y = y, x+y
		  case <-quit: // wait for 'quit' to be updated
			   fmt.Println("quit")
			   return
		}
	}
}

func main() {
	
	// define a channel 'c' to store the result of fibonacci 
	c := make(chan int)
	
	// define a channel 'quit' to alert the process was finished
	quit := make(chan int)
	
	// define a goroutine that will print 10 fibonacci numbers
	go func() {
		for i := 0; i < 10; i++ {
			fmt.Println(<-c) // request the channel value 'c' ["print 10 receivers c"]
		}
		quit <- 0 // send 0 to channel quit to finish the program
	}()
	
	fibonacci(c, quit)
}