Is the STL priority queue a proper implementation of a heap with siftup
algorithm etc ? How do you implement an STL priority queue (link to an
example) ? Is there a resort method, why ?
Thanks
4  10369  vf***@talktalk. net wrote:
Is the STL priority queue a proper implementation of a heap with siftup
algorithm etc ?
Yes.
How do you implement an STL priority queue (link to an
example) ?
#include <queue>
std::priority_q ueue<intq;
You use push() to add members,
top() to get the top element and pop() to remove the top element.
Is there a resort method, why ?
Yes, but you don't need it. It's for people implementing their own
heaps for various reasons.
Thanks red floyd, are you related to pink ? Are you back at the hotel ?
vf***@talktalk. net wrote:
Is the STL priority queue a proper implementation of a heap with siftup
algorithm etc ? How do you implement an STL priority queue (link to an
example) ? Is there a resort method, why ?
Thanks
Technically a priority queue is an abstract data type whereas a heap is
a specific data structure which *can* be used to implement a priority
queue. AFAIK, there's no requirement or guarantee that the priority
queue is implemented as a heap (though in practice you're likely to find
that it is).
There is no resort method in the priority_queue interface.
Mark P wrote:
>
There is no resort method in the priority_queue interface.
No, but there is std::make_heap( ), if you want to roll your own priority
queue. Also, priority_queue is available for private inheritance (the
underlying container is a protected member). This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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Hi,
I'm having some compiler problems when I try to use make_heap(),
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I am compiling my code on gcc version 3.3.1 (SuSE Linux).
I am using the heap related methods to create a priority queue on a
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The problem is that the compiler says that I have to implement the
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