上一个 go 的版本
```
package main

import (
"fmt"
"sync"
"time"
)

var l = sync.Mutex{}
var cond = sync.NewCond(&l)

var turn = 0

func main() {
s := []string{"A", "B", "C"}
for _, item := range s{
go func(x string) {
for i := 0; i < 10; i++ {
l.Lock()
if s[turn] == x{
// my turn
fmt.Println(i, x)
turn = (turn+1) % 3
cond.Broadcast()
}
cond.Wait()
l.Unlock()
}
}(item)
}
time.Sleep(time.Hour)
}

```