如何使用 Go 语言将二维数组转换为目录结构？

import (
    "encoding/json"
    "strings"
)

type Node struct {
    Name  string
    Value string
    Child map[string]Node
}

func main() {
    keys := [][]string{
        []string{"answer", "aa", "bb"},
        []string{"answer", "aa", "cc"},
        []string{"question", "book1"},
        []string{"question", "book1", "answer"},
        []string{"question", "book1", "answer", "name1"},
        []string{"question", "book1", "answer", "name2"},
    }

    root := Node{
        Name:  "",
        Value: "",
        Child: make(map[string]Node),
    }

    for _, key := range keys {
        t := &root
        for _, k := range key {
            if _, has := t.Child[k]; has {
                t = &t.Child[k]
            } else {
                t.Child[k] = Node{
                    Name:  k,
                    Value: strings.Join(key, ":"),
                    Child: make(map[string]Node),
                }
                t = &t.Child[k]
            }
        }
    }
    r, _ := json.Marshal(&root)
    println(string(r))
}