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\title{CS 141: Advanced Topics in Algorithms \\ Spring 2006 \\ Homework
    John and Michael}
\author{John McCullough}
\date{Due:  Thursday, April 20}
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\begin{enumerate}

  \item \Points{$9.\overline{9}$} \Name{Prove the Sibling Property!}

In class we used the result that a code tree is a Huffman Tree if and
only if it maintains the sibling property.  If you recall, the sibling
property is stated as:
\begin{quote}
A binary code tree has the sibling property if each node (except the
root) has a sibling and if the nodes can be listed in order of
non-increasing weight with each node being adjacent to its sibling in
this ordering.
\end{quote}
Because we are busy students, we would like you to prove this for us.
Don't forget to show both directions!

\end{enumerate}

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