Multimap

[Josh]

I've never used the std::multimap before, and have use for it now.

 

Here's the class:

	class Actor : public Object
{
public:
	std::multimap<std::string,Output> outputs;
};

I need to add an object into the map, without removing other objects that use the same key:

	void Actor::AddOutput(Actor* target,const std::string& outputname, const std::string& inputname)
{
	Output out;
	out.target = target;
	out.functionname = inputname;
	outputs.insert(pair<std::string,Output>(outputname,out));????????????
}

And I want to iterate through all objects for a given key:

void Actor::CallOutputs(const std::string& name)
{
	/*Output out;
	out = (outputs.find(name))->Second
	out.Call();???????*/
}

Anyone know how to do this?

[Canardia]

#include <string.h>
#include <iostream>
#include <map>
#include <utility>

using namespace std;

int main()
{
   // Compare (<) function not required since it is built into string class.
   // else declaration would comparison function in multimap definition.
   // i.e. multimap<string, int, compare> m;

   multimap<string, int> m;

   m.insert(pair<string, int>("a", 1));
   m.insert(pair<string, int>("c", 2));
   m.insert(pair<string, int>("b", 3));
   m.insert(pair<string, int>("b", 4));
   m.insert(pair<string, int>("a", 5));
   m.insert(pair<string, int>("b", 6));

   cout << "Number of elements with key a: " << m.count("a") << endl;
   cout << "Number of elements with key b: " << m.count("b") << endl;
   cout << "Number of elements with key c: " << m.count("c") << endl;

   cout << "Elements in m: " << endl;
   for (multimap<string, int>::iterator it = m.begin(); it != m.end(); ++it)
   {
       cout << "  [" << (*it).first << ", " << (*it).second << "]" << endl;
   }

   pair<multimap<string, int>::iterator, multimap<string, int>::iterator> ppp;

   // equal_range( returns pair<iterator,iterator> representing the range
   // of element with key b
   ppp = m.equal_range("b");

   // Loop through range of maps of key "b"
   cout << endl << "Range of \"b\" elements:" << endl;
   for (multimap<string, int>::iterator it2 = ppp.first; it2 != ppp.second; ++it2)
   {
        cout << "  [" << (*it2).first << ", " << (*it2).second << "]" << endl;
   }

   // Can't do this (??)
   // cout << ppp.first << endl;
   // cout << ppp.second << endl;

   m.clear();
}