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<b>Data Structures and Algorithms
with Object-Oriented Design Patterns in C++</b><br>
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<H1><A NAME="SECTION0014000000000000000000">Dynamic Storage Allocation: The Other Kind of Heap</A></H1>
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In the preceding chapters when analyzing an algorithm involving
dynamically allocated storage,
we assume that the time taken
to acquire or to release storage is bounded by a constant.
Specifically, Axiom <A HREF="page46.html#axiomvi" tppabs="http://dictator.uwaterloo.ca/Bruno.Preiss/books/opus4/html/page46.html#axiomvi"><IMG ALIGN=BOTTOM ALT="gif" SRC="cross_ref_motif.gif" tppabs="http://dictator.uwaterloo.ca/Bruno.Preiss/books/opus4/icons/cross_ref_motif.gif"></A> in Chapter <A HREF="page34.html#chapmodel" tppabs="http://dictator.uwaterloo.ca/Bruno.Preiss/books/opus4/html/page34.html#chapmodel"><IMG ALIGN=BOTTOM ALT="gif" SRC="cross_ref_motif.gif" tppabs="http://dictator.uwaterloo.ca/Bruno.Preiss/books/opus4/icons/cross_ref_motif.gif"></A> states that
the running time of operator <tt>new</tt> is a constant, <IMG WIDTH=23 HEIGHT=15 ALIGN=MIDDLE ALT="tex2html_wrap_inline58579" SRC="img128.gif" tppabs="http://dictator.uwaterloo.ca/Bruno.Preiss/books/opus4/html/img128.gif" >,
and that the running time of operator <tt>delete</tt> is also a constant,
<IMG WIDTH=41 HEIGHT=15 ALIGN=MIDDLE ALT="tex2html_wrap_inline58581" SRC="img129.gif" tppabs="http://dictator.uwaterloo.ca/Bruno.Preiss/books/opus4/html/img129.gif" >.
<P>
But is this really so?
To answer this question,
we consider in this chapter the dynamic management of a pool of memory.
In particular,
we consider several different implementations for the operators
<tt>new</tt> and <tt>delete</tt>
and we show that the assumptions of constant running times
are not always valid.
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<LI> <A NAME="tex2html7065" HREF="page426.html#SECTION0014300000000000000000" tppabs="http://dictator.uwaterloo.ca/Bruno.Preiss/books/opus4/html/page426.html#SECTION0014300000000000000000">Doubly Linked Free Storage</A>
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