how to start use nested STL container

[guorke]

Hi,all
I want to learn something about nested stl containers, but i
can't find any tips on it(such as
faq, c++ books etc), so anybody can give a good link (or good book)
which talk about it?

It's peffect if it have some examples.

Thanks all.

 

[=?ISO-8859-1?Q?Erik_Wikstr=F6m?=]

Hi,all
I want to learn something about nested stl containers, but i
can't find any tips on it(such as
faq, c++ books etc), so anybody can give a good link (or good book)
which talk about it?

It's peffect if it have some examples.

There's really not much to it, you just parametrise the outer container
with the inner and start using it.

std::map<int, std::vector<double> > m;

m[1].push_back(1.5);
m[1].push_back(1.4);
m[2].push_back(3.56);
m[3].push_back(13.65);
m[1].push_back(2.5);

 

[guorke]

Ok,
but no anybody knows how a link about this?
like, map<int,map<int,int> > mapf; I still not know how to insert into
mapf.

so i still need some tips about nested containers.
Thanks & Best Wishes.

 

[Ian Collins]

guorke wrote:

Please retain context.

Ok,
but no anybody knows how a link about this?
like, map<int,map<int,int> > mapf; I still not know how to insert into
mapf.

Just follow the normal rules for inserting. Maybe a typedef would make
it clearer?

typedef std::map<int,int> IntMap;

std::map<int, IntMap> mapf;

 

[guorke]

Many Thanks.
[] operator can deal with nested containers like this,
std::map<std::string , std::map<std::string , std::string> > m_values;
std::map<std::string , std::map<std::string , int> > m_lines;
const std::string section;
const std::string key;
const std::string value;
int line =0;

m_values[section][key] = value;
line =m_lines[section][key];
How can i understand it?

 

[guorke]

Many Thanks.
[] operator can deal with nested containers like this,
std::map<std::string , std::map<std::string , std::string> > m_values;
std::map<std::string , std::map<std::string , int> > m_lines;
const std::string section;
const std::string key;
const std::string value;
int line =0;

m_values[section][key] = value;
line =m_lines[section][key];
How can i understand it?

 

[BobR]

Ok,
but no anybody knows how a link about this?
like, map<int,map<int,int> > mapf; I still not know how to insert into
mapf.

so i still need some tips about nested containers.
Thanks & Best Wishes.

{
std::map<int, std::map<int, int> > mapf;
std::map<int, int> Imapf;
Imapf[1] = 1;
mapf[1] = Imapf;
mapf[1][2] = 2;
std::cout<<"mapf[1][2] ="<<mapf[1][2]<<std::endl;
mapf[1].insert( std:air<int, int>(3, 3) );
cout<<"mapf[1][3] ="<<mapf[1][3]<<std::endl;
}
/* -output-
mapf[1][2] =2
mapf[1][3] =3
*/

Learn each container/sequence separately. Then worry about combining them.

Dinkumware:
http://www.dinkumware.com/manuals/.

 

[guorke]

Many Thanks.
[] operator can deal with nested containers like this,
std::map<std::string , std::map<std::string , std::string> > m_values;
std::map<std::string , std::map<std::string , int> > m_lines;
const std::string section;
const std::string key;
const std::string value;
int line =0;

m_values[section][key] = value;
line =m_lines[section][key];
How can i understand it?

 

[Ian Collins]

guorke wrote:

Where's the context?

Many Thanks.

You don't have to post 3 times.

[] operator can deal with nested containers like this,
std::map<std::string , std::map<std::string , std::string> > m_values;
std::map<std::string , std::map<std::string , int> > m_lines;
const std::string section;
const std::string key;
const std::string value;
int line =0;

m_values[section][key] = value;
line =m_lines[section][key];
How can i understand it?

By practice? Break the expression down and follow each part, only you
can do the understanding.

 

[guorke]

Many Thanks.
[] operator can deal with nested containers like this,
std::map<std::string , std::map<std::string , std::string> > m_values;
std::map<std::string , std::map<std::string , int> > m_lines;
const std::string section;
const std::string key;
const std::string value;
int line =0;

m_values[section][key] = value;
line =m_lines[section][key];
How can i understand it?