Am I right in assuming that adding/removing elements to an std::map does not effect the other elements (ie cause them to be relocated in memory) and so that the following is safe:

I looked at various sites with info on the container but only found out about the cases where iterators are invalidated, which I already know...

```
std::map<std::string,std::string> map;
PopulateMap(map);
std::string &a= map["x"];
AddMoreData(map);
RemoveRandomKeysExceptX(map);
map["x"] = "foo";
std::cout << a << " " << map["x"] << std::endl;//prints "foo foo"
a = "bar";
std::cout << a << " " << map["x"] << std::endl;//prints "bar bar"

```

I tested some similar code on VC9, which seems to work however that doesn't mean I didn't just get lucky or that it doesn't vary across compilers.