Adding distinct pairs into a set

I am trying to insert a few pairs of 'int' into a set, these pairs don't have any order; that is, (1,2) = (2,1). So simply I do as follows,

typedef pair<int, int> pairs; 

set<pairs> Set;
pair <int,int> myPair;

// adding pairs:
myPair=pair<int,int>(0,1);
pathSet.insert(myPair);
myPair=pair<int,int>(0,2);
pathSet.insert(myPair);
myPair=pair<int,int>(1,0);
pathSet.insert(myPair);

So I end up a set like {(0,1), (0,2) , (1,0)}. I want to have {(0,1), (0,2)}. How can I avoid duplicate? Is there anyway? Is there any better ADT like std::unordered_set in terms of efficiency in comparison with 'set'?

Thanks!