shared_ptr in priority_queue: how to make it work

hi, all
Here is what I want to do: to wrap my self defined class in a
shared_ptr and then insert it into the priority_queue. The
priority_queue should pump the least element of the self defined class
first. To make it simple, here is the toy code.

myClass.h
------------------------------------------
#ifndef MYCLASS_H
#define MYCLASS_H

class myClass {
   public:
                 double a;
                 myClass(double a) {
                         this->a = a;
                 }

                 bool operator<(const myClass & right) const { //the
comparison is
"reversed" in order to pop smallest first
                         return a > right.a;
                 };
                 bool operator>(const myClass & right) const {
                         return a < right.a;
                 }
                 bool operator<=(const myClass & right) const {
                         return a >= right.a;
                 }
                 bool operator>=(const myClass & right) const {
                         return a <= right.a;
                 }
};

#endif
---------------------------------------------------//over

Foo.cpp
-------------------------------------------------
#include <vector>
#include <queue>
#include <deque>
#include <boost/shared_ptr.hpp>
#include "myClass.h"
#include <iostream>

using namespace boost;
using namespace std;

int main(){
         priority_queue<shared_ptr<myClass> > pq;
         shared_ptr<myClass> temp(new myClass(1));
         pq.push(temp);
         temp.reset(new myClass(2));
         pq.push(temp);
         temp.reset(new myClass(3));
         pq.push(temp);
         while (!pq.empty()){
                 temp = pq.top();
                 cout<<temp->a<<endl;
                 pq.pop();
         }
}

----------------------------------------------------//over

I was expecting the priority_queue to pop 1 first and 3 last. However,
it pops 3 first and 1 last. (If I input 3,2,1 in a sequence, then the
output will be 1,2,3. So it seems that there is no sorting at all) My
real program is more complex than this and I have the reason to use the
shared_ptr. So, directly insert the numbers into the priority_queue is
not a solution. Can someone help me to fix the problem? Thanks ahead.

zl2k

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