Why do we say that the call of virtual function cannot be determined in compiling time?
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  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/13954950/if-virtual-table-is-created-in-compile-time-then-why-do-we-call-this-as-a-run-t">If virtual table is created in compile time, then why do we call this as a run time polymorphism?</a>  </p>
</blockquote>



<p>We say that the call of virtual function in C++ is determined in run time, not in compile time. So I think I am not clear about the difference between compile time and run time. In my rough thought, everything should be determined in compile time... Who could help on this question? Thanks！</p>
