how to build a recursive map ?

[jose luis fernandez diaz]

Hi,

When I want build a tree I define the structure below:

struct node
{
string data;
node *leaf;
node *right;
};


I want to define a map where each element is a map. Something similar to:

map<string, map *> m1;


Any idea ?

Thanks,
Jose Luis.

[Karl Heinz Buchegger]

Re: how to build a recursive map ?

jose luis fernandez diaz wrote:[color=blue]
>
> I want to define a map where each element is a map. Something similar to:
>
> map<string, map *> m1;[/color]

This is not a map of maps, it is a map of pointers to maps.
Anyway: what is your problem?

lets say you have a map, which maps int to double

map< int, double >

you now want to build a map out of this, such that a string
selects the map which maps int to double.

map< string, map< int, double > >

--
Karl Heinz Buchegger
kbuchegg@gascad .at

[John Harrison]

Re: how to build a recursive map ?


"jose luis fernandez diaz" <jose_luis_fdez _diaz_news@yaho o.es> wrote in
message news:c2f95fd0.0 404200623.77eb4 25f@posting.goo gle.com...[color=blue]
> Hi,
>
> When I want build a tree I define the structure below:
>
> struct node
> {
> string data;
> node *leaf;
> node *right;
> };
>
>
> I want to define a map where each element is a map. Something similar to:
>
> map<string, map *> m1;
>
>
> Any idea ?
>
> Thanks,
> Jose Luis.[/color]

Like this

class Recursive
{
public:
...
private:
map<string, Recursive*> m1;
};

john

[jose luis fernandez diaz]

Re: how to build a recursive map ?

Karl Heinz Buchegger <kbuchegg@gasca d.at> wrote in message news:<40853AAB. 18C8762@gascad. at>...[color=blue]
> jose luis fernandez diaz wrote:[color=green]
> >
> > I want to define a map where each element is a map. Something similar to:
> >
> > map<string, map *> m1;[/color]
>
> This is not a map of maps, it is a map of pointers to maps.
> Anyway: what is your problem?
>
> lets say you have a map, which maps int to double
>
> map< int, double >
>
> you now want to build a map out of this, such that a string
> selects the map which maps int to double.
>
> map< string, map< int, double > >[/color]

I need something like this:

template<class key, class T, . . .>
class map
{
typedef Key key_type;
// typedef T mapped_type;
typedef map *mapped_type;

. . .
}

map<string> m1;
m1["one"] = NULL;
m2["two"] = m1;

but I think that it is not posible.

I tried to simulate it with:

map<string, map<string, map<string ... string> . . . > m_n;

m_1["one"] = "zero";
m_2["two"] = m1["one];
.. . .
m_n["n"] = n_n_1["n-1"];


but this is ugly.

Regards,
Jose Luis.

[Dan Cernat]

Re: how to build a recursive map ?

jose_luis_fdez_ diaz_news@yahoo .es (jose luis fernandez diaz) wrote in message news:<c2f95fd0. 0404200623.77eb 425f@posting.go ogle.com>...[color=blue]
> Hi,
>
> When I want build a tree I define the structure below:
>
> struct node
> {
> string data;
> node *leaf;
> node *right;
> };
>
>
> I want to define a map where each element is a map. Something similar to:
>
> map<string, map *> m1;
>
>
> Any idea ?
>
> Thanks,
> Jose Luis.[/color]

try

map<string, void*>

and cast the void* to a map<string, void*> internally and so on. you
stop when the pointer is null.

to add elements to such thing:

map<string, void*> leaf1, leaf2;
leaf1["aa"] = 0;
laef2["bb"] = 0;

map<string, void*> node1;
node1["leaf1"] = leaf1;
node1["leaf2"] = leaf2;

dan