Go交叉打印

package main

import (
	"fmt"
	"sync"
)

var wg sync.WaitGroup
var number, letter = make(chan bool), make(chan bool)

func printInt() {
	defer wg.Done()
	i := 1
	for {
		_, ok := <-number
		if !ok {
			close(letter)
			return
		}
		fmt.Printf("%d%d", i, i+1)
		i += 2
		letter <- true
	}
}

func printLetter() {
	defer wg.Done()
	l := 'A'

	for {
		_, _ = <-letter
		if l > 'Z' {
			close(number)
			return
		}
		fmt.Printf("%c%c", l, l+1)
		l += 2
		number <- true
	}
}

func main() {
	wg.Add(1)
	wg.Add(1)
	go printInt()
	go printLetter()
	number <- true
	wg.Wait()
}