2 STL questions

1)Is there some way I can make a std:riority_queue which pops in ascending order ?
I know that it uses the '<' operator to sort while poping. So if overload '<' operator do '>' , it might work. But it is wrong to do that.

2) is there an STL search tree or do I have make one?
If there is no search tree, how do I search in a queue sine i dont see any mem-function or iterators access other elements in between 'front' and 'back'.

The standard definition of priority_queue is of the form;

Code:

template<class T, class Container = vector<T>, class Compare = less<typename Container<T>::value_type> >
priority_queue
{
    // etc etc.
}

In response to your first question, create an object of type;

Code:

std::priority_queue<T, std::vector<T>, greater<typename std::vector<T>::value_type> >;

A few typedefs would probably be helpful in achieving this

A protected member of priority_queue is the underlying container (which is a vector<T> by default) used by the priority_queue (it's name is c). So create a class that is derived from your priority_queue<> and provide that derived classes with public member functions that provide controlled access to the underlying container. Keep in mind that, as priority_queue<> provides no virtual member functions, there are some constraints on how you can use the derived type.

1)

Code:

#include <iostream>
#include <queue>
#include <functional> //greater<>()

using namespace std;

int main()
{
	priority_queue<int, vector<int>, greater<int> > q;

	q.push(1);
	q.push(4);
	q.push(3);

	while(!q.empty())
	{
		cout<<q.top()<<" ";
		q.pop();
	}
	
	cout<<endl;
	
	return 0;
}

2) Have you considered a set<>?

2) Have you considered a set<>

Yes I read about those in older posts. but they where reagrding searching in Log(n) time or so.
the thing is that I don't just want to search, but also, given the address of a leaf, I want to back track it to the root. ie, I want all the elements in sequence, lying in the path connecting root and given leaf.

I will try the thing with the priority queue. But i didn't notice the third template argument in my header file in the morning. I saw only the first two. But Iwill check again.
Thanks grumpy, and 7stud.