Does priority_queue really produce a Heap? : <p>I am bit confused between Heap and priority_queue in C++ STL. Does priority_queue really produce a Heap?</p>

<pre>
If we insert elements in order - 5, 1, 10, 30, 20
Output for maxHeap will be: 30, 20, 5, 1, 10
While output for priority_queue will be: 30, 20, 10, 5, 1
</pre>

<p>What is the reason behind this? </p>

<p>Is priority_queue always sorted?</p>
