子域树的实现

Question

I am working on golang implementation of subdomains tags storage (looks like multimap). Not so clear for me what type of tree should I use for implement following logic:

    tree := NewTree()
    tree.AddTag("com", 1)
    tree.AddTag("google.com", 2)
    tree.AddTag("google.com", 3)
    tree.AddTag("www.google.com", 4)

    var ret []int
    ret = tree.GetTags("msn.com") // ret = [1]
    ret = tree.GetTags("www.msn.com") // ret = [1]
    ret = tree.GetTags("google.com") // ret = [1,2,3]
    ret = tree.GetTags("www.google.com") // ret = [1,2,3,4]
    ret = tree.GetTags("mail.google.com") // ret = [1,2,3]
    ret = tree.GetTags("debug.www.google.com") // ret = [1,2,3,4]

This task is different than suffix search, for example "msn.com" belongs to "com" and "www.google.com" belongs to "google.com" and "www.google.com".

If someone could to point me to c/c++/golang sources I would also appreciate.