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\documentclass[a4paper,12pt]{article}
\usepackage[english,vietnamese]{babel}
\usepackage{amsmath}
\usepackage{hyperref}
\usepackage{lmodern}
\usepackage{mathtools}

\title{Discrete Mathematics: Algorithm}
\author{Nguyễn Gia Phong---BI9-184}
\date{\dateenglish\today}

\begin{document}
\maketitle
\section{Problem 3}
The program \verb|coin.c| takes an integer $n$ from \verb|stdin| and print
the least coin exchange of $n$ cents to \verb|stdout|.

\section{Problem 4}
The program \verb|schedule.c| take an integer $n$ and $n$ integral
time intervals from \verb|stdin| and print to \verb|stdout| the chosen talks
intervals in chronological order.

\section{Problem 5}
\verb|search.c| contains two searching implementations, linear search
(\verb|lsearch|) and binary search (\verb|bsearch|).

It is trivial that \verb|lsearch| has \verb|nmemb| or $\Theta(n)$
time complexity.

For \verb|binary_search| (which is wrapped by \verb|bsearch|),
the time complexity (in term of number of comparisons) is can be seen as
\begin{align*}
  T(n) &= T\left(\frac{n}{2}\right) + \Theta(1)\\
  &= T\left(\frac{n}{2}\right) + \Theta\left(n^{\log_2 1}\right)
\end{align*}
since \verb|mid = (lo + high) / 2)|.
\pagebreak

By the master theorem\footnote{Let $a \ge 1$ and $b > 1$ be constants,
and let $T(n)$ be defined on the nonnegative integers by the recurrence
\[T(n) = aT\left(\frac{n}{b}\right) + \Theta\left(n^{\log_b a}\right)\]
where $n/b$ is interpreted as either $\lfloor n/b\rfloor$ or $\lceil n/b\rceil$,
then \[T(n) = \Theta\left(n^{\log_b a}\lg n\right)\]},
\[T(n) = \Theta\left(n^{\log_2 1}\lg n\right) = \Theta(\lg n)\]

\section{Copying}
This report along with the source files are licensed under a
\href{https://creativecommons.org/licenses/by-sa/4.0/}{Creative Commons
Attribution-ShareAlike 4.0 International License}.
\end{document}