This program illustrates a simple priority queue of integers, including a
default constructor, a copy constructor, and the push(), pop(), top(), empty()
and size() member functions of the STL priority_queue interface.
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The priority queue pq1 contains 5 elements.
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Here they are, in priority order:
Popping: 46
Popping: 35
Popping: 27
Popping: 19
Popping: 11
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Before displaying the contents of the priority queue pq2, which was a copy
of pq1, we add to it the values 75 and 5, in that order.
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Now here are the new contents of pq2, in priority order:
Popping: 75
Popping: 46
Popping: 35
Popping: 27
Popping: 19
Popping: 11
Popping: 5
Press Enter to continue ...