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% !TEX program = xelatex
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\documentclass[dvipsnames,14pt,t,xelatex]{beamer}
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\usepackage{chessboard}
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\usepackage[LSBC4,T1]{fontenc}
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\usepackage{../slides}
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\usepackage{../graphics}
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\usepackage{../langs}
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% \usepackage{../data}
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\hfuzz=220pt
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%\setmonofont[Scale=.88]{Consolas}
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%\newfontfamily{\consolas}{Consolas}
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\lstset{language=Scala,
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style=mystyle,
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numbersep=0pt,
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numbers=none,
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xleftmargin=0mm}
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\newcommand{\bl}[1]{\textcolor{blue}{#1}}
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% beamer stuff
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\renewcommand{\slidecaption}{PEP (Scala) 02, King's College London}
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\begin{document}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{%
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\begin{tabular}{@ {}c@ {}}
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\\[5mm]
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\huge PEP Scala (2)
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\end{tabular}}
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\normalsize
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\begin{center}
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\begin{tabular}{ll}
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Email: & christian.urban at kcl.ac.uk\\
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Office: & N\liningnums{7.07} (North Wing, Bush House)\bigskip\\
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Slides \& Code: & KEATS\bigskip\\
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Office Hours: & Thursdays 12:00 -- 14:00\\
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Additionally: & (for Scala) Tuesdays 10:45 -- 11:45\\
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\end{tabular}
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\end{center}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c,fragile]
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\frametitle{My Scala Version}
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\begin{lstlisting}[language={},numbers=none,
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basicstyle=\ttfamily\small,xleftmargin=-2mm]
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$ scala
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Welcome to Scala 2.13.1 (Java HotSpot(TM)
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64-Bit Server VM, Java 9). Type in expressions
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for evaluation. Or try :help.
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scala>
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\end{lstlisting}%$
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\bigskip\bigskip
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With older versions you will get strange results with my reference implementation.
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c,fragile]
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\frametitle{Reference Implementation}
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Keep your implementation and my reference implementation separate.\bigskip
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\begin{lstlisting}[language={},numbers=none,
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basicstyle=\ttfamily\small,xleftmargin=-2mm]
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$ scala -cp collatz.jar
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scala> CW6a.collatz(6)
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res0: Long = 8
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scala> import CW6a._
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scala> collatz(9)
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res1: Long = 19
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\end{lstlisting}%$
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{Preliminary Part 7}
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\Large
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\[
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\texttt{overlap}(d_1, d_2) = \frac{d_1 \cdot d_2}{max(d_1^2, d_2^2)}
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\]\bigskip
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\large
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\quad{}\;where \;$d_1^2$\; means \;$d_1 \cdot d_1$\; and so on
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c]
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\frametitle{Assignments}
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Don't change anything with the templates!\bigskip
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Avoid at all costs:
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\begin{itemize}
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\item \texttt{var}
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\item \texttt{return}
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\item \texttt{ListBuffer}
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\item \texttt{mutable}
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\item \texttt{.par}
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\end{itemize}\pause\bigskip
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\mbox{}\hfill\textit{``Scala --- \underline{S}lowly \underline{c}ompiled
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\underline{a}cademic \underline{la}nguage''}\smallskip\\
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\mbox{}\hfill\textit{ --- a joke(?) found on Twitter}\bigskip
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{Email: Hate 'val'}
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\mbox{}\\[-25mm]\mbox{}
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\begin{center}
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\begin{bubble}[10.5cm]
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Subject: \textbf{Hate '\textbf{\texttt{val}}'}\hfill 01:00 AM\medskip\\
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Hello Mr Urban,\medskip\\
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I just wanted to ask, how are we suppose to work
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with the completely useless \textbf{\texttt{val}}, that can’t be changed ever? Why is
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this rule active at all? I’ve spent 4 hours not thinking on the
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coursework, but how to bypass this annoying rule. What’s the whole
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point of all these coursework, when we can’t use everything Scala
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gives us?!?\medskip\\
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Regards.\\
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\mbox{}\hspace{5mm}\textcolor{black!50}{<<deleted>>}\\
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\end{bubble}
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\end{center}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\def\firstcircle{(0,0) circle (1.4cm)}
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\def\secondcircle{(0:2cm) circle (1.4cm)}
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\colorlet{circle edge}{blue!50}
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\colorlet{circle area}{blue!20}
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\tikzset{filled/.style={fill=circle area, draw=circle edge, thick},
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outline/.style={draw=circle edge, thick}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c,fragile]
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\frametitle{Par: Intersections}
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\begin{textblock}{6}(1,2)
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\begin{tikzpicture}
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\draw[outline] \firstcircle node {$A$};
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\node[anchor=south] at (current bounding box.north)
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{$A = \{1,2,3,\ldots,1000\}$};
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\end{tikzpicture}
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\end{textblock}
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\begin{textblock}{6}(8,2)
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\begin{tikzpicture}
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\draw[outline] \secondcircle node {$B$};
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\node[anchor=south] at (current bounding box.north)
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{$B = \{1,5,9,13,\ldots,997\}$};
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\end{tikzpicture}
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\end{textblock}
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\begin{textblock}{6}(3.3,9)
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\begin{tikzpicture}
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\begin{scope}
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\clip \firstcircle;
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\fill[filled] \secondcircle;
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\end{scope}
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\draw[outline] \firstcircle node {$A$};
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\draw[outline] \secondcircle node {$B$};
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\node[anchor=north] at (current bounding box.south)
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{How many elements are in $A \cap B$?};
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\end{tikzpicture}
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\end{textblock}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{For-Comprehensions Again}
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\begin{center}
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\begin{tikzpicture}[scale=1,
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node/.style={
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rectangle,rounded corners=3mm,
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very thick,draw=black!50,
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minimum height=18mm, minimum width=20mm,
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top color=white,bottom color=black!20}]
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\node (A0) at (0.1,0) {\texttt{\textcolor{purple}{\textbf{for}} (\alert<2->{n} <- List(}};
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\node (A1) at (2.3,0) {\texttt{\phantom{,}1,}};
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\node (A2) at (3.2,0) {\texttt{\phantom{,}2,}};
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\node (A3) at (4.1,0) {\texttt{\phantom{,}3,}};
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\node (A4) at (5.0,0) {\texttt{\phantom{,}4,}};
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\node (A5) at (5.9,0) {\texttt{\phantom{))}5))}};
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\node (A6) at (8,0) {\texttt{\textcolor{purple}{\textbf{yield}} \alert<2->{n\,*\,n}}};
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\onslide<2->{
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\node (B0) at (1.4,-3) {\texttt{List(}};
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\node (B1) at (2.3,-3) {\texttt{\phantom{,}1,}};
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\node (B2) at (3.6,-3) {\texttt{\phantom{,}4,}};
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\node (B3) at (4.9,-3) {\texttt{\phantom{,}9,}};
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\node (B4) at (6.2,-3) {\texttt{\phantom{,}16,}};
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\node (B5) at (7.5,-3) {\texttt{\phantom{,}25)}};}
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\onslide<2->{
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\draw [->,line width=1mm] (A1.south) -- (B1.north);
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\draw [->,line width=1mm] (A2.south) -- (B2.north);
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\draw [->,line width=1mm] (A3.south) -- (B3.north);
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\draw [->,line width=1mm] (A4.south) -- (B4.north);
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\draw [->,line width=1mm] (A5.south) -- (B5.north);}
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\onslide<2->{
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\node (Q1) at (-0.45,-0.1) {};
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\node (Q2) at (-0.45,-2.8) {};
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\node (Q3) at (-0.45,-2.95) {\alert<2->{\texttt{n\,*\,n:}}};
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\draw [->,red,line width=1mm] (Q1.south) -- (Q2.north);}
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\end{tikzpicture}
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\end{center}
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\onslide<3>{This is for when the for-comprehension\\ \textbf{yields / produces} a result.}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{For-Comprehensions Again}
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\begin{center}
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\begin{tikzpicture}[scale=1,
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node/.style={
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rectangle,rounded corners=3mm,
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very thick,draw=black!50,
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minimum height=18mm, minimum width=20mm,
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top color=white,bottom color=black!20}]
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\node (A0) at (0,0)
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{\texttt{\textcolor{purple}{\textbf{for}} (n <- List(1, 2, 3, 4, 5))
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\textcolor{purple}{\textbf{yield}} n\,*\,n}};
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\node (A1) at (0,-1.5) {\LARGE\textbf{vs}};
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\node (A2) at (0,-3)
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{\texttt{\textcolor{purple}{\textbf{for}} (n <- List(1, 2, 3, 4, 5)) println(n)}};
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\end{tikzpicture}
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\end{center}\bigskip
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The second version is in case the for \textbf{does not}
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produce any result.
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[t]
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\frametitle{Why Scala? No null!}
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\begin{itemize}
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\item \large {\bf You can avoid \textcolor{blue}{\texttt{null}}}:
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\end{itemize}
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\begin{textblock}{6}(1,5)
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\begin{bubble}[10.5cm]\small
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``I call it my billion-dollar mistake. It was the invention of
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the null reference in 1965. At that time, I was designing the
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first comprehensive type system for references in an object
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oriented language (ALGOL W). My goal was to ensure that all use
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of references should be absolutely safe, with checking performed
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automatically by the compiler. But I couldn't resist the
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temptation to put in a null reference, simply because it was so
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easy to implement. This has led to innumerable errors,
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vulnerabilities, and system crashes, which have probably caused
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a billion dollars of pain and damage in the last forty years.''
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\hfill Sir Tony (Hoare)
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\end{bubble}
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\end{textblock}
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\begin{textblock}{5}(12.5,1.9)
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\includegraphics[scale=0.05]{../pics/hoare.jpg}\\
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\end{textblock}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\begin{frame}[c]
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\frametitle{\begin{tabular}{c}\\[0cm]\alert{Questions?}\end{tabular}}
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\begin{center}
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\begin{tabular}[t]{@{}l@{}l@{}}
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\includegraphics[scale=0.1]{../pics/mand4.png} & \hspace{4mm}
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\raisebox{0mm}{\includegraphics[scale=0.1]{../pics/mand3.png}}
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\end{tabular}
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\end{center}
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\begin{center}
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My Office Hours: Thursdays 12 -- 14\\
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And specifically for Scala: Tuesdays 10:45 -- 11:45
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\end{center}
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\end{frame}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\end{document}
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%%% Local Variables:
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%%% mode: latex
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%%% TeX-master: t
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%%% End:
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