Need a bit help with std::map and / or multimaps and algorithm

[BytePtr]

Hello.

Im stuck with some problem(s).
Currently i have a std::map like this:

map<int, int> mymap;

In my procedure i add some items to this. When i have no duplicates for keys, all seems to work.
Few examples of my keys and values (just examples) just to get the idea:
Without duplicate keys:

mymap[257]=10;
mymap[94]=25;
mymap[98]=55;
mymap[21]=11;

When i need to work with duplicates (when one key can be used more than 1 time but different value)

mymap[257]=10;
mymap[94]=25;
mymap[98]=55;
mymap[98]=70;
mymap[21]=11;

I know that for duplicate keys with different values i should use multimap.

Lets say i switch to multimap..

Now if you look the duplicates example above, you see that when i need to get value of 98 i get it with:

int i = mymap[98];
// i is now: 55

Whats even more important, sometimes i need the latest value of the specific key

In this case:

int i = mymap[98];
// i MUST be 70

Is there any function for multimap or algorithm that returns me the latest specific "KEY" from multimap ?
Or there some other containers that could help me?

If its possible i would like to avoid multimap completely. I have seen that it differs from map pretty a lot and causes troubles in many areas.

What about pairs?
I can use C++11, boost and other latest technology if that matters.

TIA for any tip or help.

[Paul McKenzie]

Why not one of these?

std::map<int, std::vector<int> >
std::map<int, std::list<int> >
std::map<int, std::deque<int> >
std::map<int, std::stack<int>  >

Regards,

Paul McKenzie

[BytePtr]

Thank you for the reply.
You gave me idea.

I did function like this:

map<int, stack<int> > asi;

int getLASTcmdindexfor(int commandid)
{
	int tmp=-1;
	auto it= asi.find(commandid);
	if(it==asi.end()) return tmp;
		if(!asi[commandid].empty()){
			tmp=asi[commandid].top();
			asi[commandid].pop();	
		}		
	return tmp;
}

I pass him "commandid" and depending on how many specific "commandid" values in the map are, it returns me the INDEX for the latest one each time i call it, until there are no more of them in stack.
And if there are no more specific "commandid"s it returns -1, indicating that there are no more such commands.

I just tested this in simple console app and seems to work fine. I will put this now into my primary app and will see how it works there.

	asi[94].push(6);
	asi[94].push(7);
	
	asi[95].push(8);
	asi[95].push(9);
	
	

	
	cout << "Nr of lines for 94: " << asi[94].size() << endl;
	
	cout <<getLASTcmdindexfor(94) << endl;
	cout <<getLASTcmdindexfor(94) << endl;
	cout <<getLASTcmdindexfor(95) << endl;
	cout <<getLASTcmdindexfor(95) << endl;

Output:

Nr of lines for 94: 2
7
6
9
8

EDIT
Made it a bit generic:

template <class Container>
int getLASTcmdindexfor(Container &inmap, int commandid)
{
	int tmp=-1;
	auto it= inmap.find(commandid);
	if(it==inmap.end()) return tmp;
		if(!inmap[commandid].empty()){
			tmp=inmap[commandid].top();
			inmap[commandid].pop();	
		}		
	return tmp;
}

[D_Drmmr]

Is there any function for multimap or algorithm that returns me the latest specific "KEY" from multimap ?

Have a look at lower_bound, upper_bound and equal_range.