go语言学习--go中的map切片

//定义一个结构 
type Car struct { 
    Brand string 
    Age int 
} 
 
func Pluck() map[int][]Car { 
    carMap := make(map[int][]Car) 
    carArr := make([]Car, 0) 
    carArr = append(carArr, Car{ 
        Brand: "audi", 
        Age: 1, 
    }) 
    carMap[1] = carArr 
    //如果存在键,则添追加数据 
    child, ok := carMap[1] 
    if ok { 
        child = append(child, Car{ 
            Brand:"QQ", 
            Age:5, 
        }) 
        carMap[1] = child 
    } else {//第一次添加数据 
        carArr := make([]Car, 0) 
        carArr = append(carArr, Car{ 
            Brand: "audi", 
            Age: 1, 
        }) 
        carMap[1] = carArr 
    } 
    return carMap 
} 
func main() { 
    rs := Pluck() 
    for _, item := range rs { 
        for _, child := range item { 
            fmt.Println(child.Brand) 
        } 
    } 
}