\documentclass[11pt]{article}
\usepackage{times}
\usepackage{fancyheadings}
\pagestyle{fancy}
\usepackage{pifont} % for fancy bullets

\newcommand{\headerfont}{\fontfamily{phv}\fontseries{b}\fontshape{n}%
\fontsize{10}{12pt}\selectfont}
\newcommand{\ttb}{\fontfamily{pcr}\fontseries{b}\fontshape{n}%
\fontsize{12}{14pt}\selectfont}
\newcommand{\ttsb}{\fontfamily{pcr}\fontseries{b}\fontshape{n}%
\fontsize{8}{10pt}\selectfont}
\newcommand{\tts}{\fontfamily{pcr}\fontseries{m}\fontshape{n}%
\fontsize{8}{10pt}\selectfont}
\newcommand{\largebold}{\fontfamily{ptm}\fontseries{b}\fontshape{n}%
\fontsize{14}{16pt}\selectfont}
\newcommand{\Largebold}{\fontfamily{ptm}\fontseries{b}\fontshape{n}%
\fontsize{19}{21pt}\selectfont}
\newcommand{\Largeboldital}{\fontfamily{ptm}\fontseries{b}\fontshape{it}%
\fontsize{19}{21pt}\selectfont}
\newcommand{\largeboldital}{\fontfamily{ptm}\fontseries{b}\fontshape{it}%
\fontsize{14}{16pt}\selectfont}

\newcommand{\mywidth}{6.0in}
\newcommand{\st}{\rule[-.8mm]{0mm}{2mm}}
\newcommand{\longst}{\rule[-3mm]{0mm}{2mm}}
\newcommand{\outerbaselinesep}{12.5pt}
\topmargin 0.0in
\oddsidemargin 0.25in
\evensidemargin 0.25in
\textwidth \mywidth
\textheight 8.5in
\parindent 0mm %10mm
\parskip 2.5mm

\fboxrule=0.3mm

%%%%%%%%% Headings %%%%%%%%%%%%%%%%%%%%%%%
\setlength{\headwidth}{\textwidth} % This shouldn't be needed.  ??
%\setlength{\headrulewidth}{0pt} % to eliminate rule under header

\newcommand{\currhead}{CS 1723, Exam 2, \today}
\lhead{\footnotesize \currhead}
\rhead{\footnotesize Page \thepage~~of~~\pageref{'thatsall'}\hspace{0.4mm}}
\lfoot{} \chead{} \cfoot{} \rfoot{}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}
 \sloppy

\begin{center}
{\largebold
   CS 1723,  Data Structures \\
    Fall Semester, 1998} \\
 {\largeboldital  Second Examination}
\end{center}

\baselineskip=\outerbaselinesep

\begin{enumerate}

\item 
 \begin{enumerate}
  \item Consider the following arithmetic expression, similar to
ones we used in a programming assignment  (the \# just terminates
the expression):

\hspace*{1in}\verb92+3*4#9

Give the RPN form of this expression.  What rule in C tells us
that the {\tt *} is performed before the {\tt +}? 

  \item There is a significant difference between the
   expressions

\hspace*{0.75in} \verb+4*3*2#+ and \verb+4^3^2+

Describe the difference and give the corresponding RPN.
\end{enumerate}

\item  Consider the following C code, which reads "words" from {\tt stdin}
and inserts them onto a 
linked list.  Supply the code for the missing functions
{\tt printlist}, {\tt printreverse}
 and {\tt insert}.  {\tt printlist} should just
chase down the list, printing words as it encounters them.
{\tt printreverse} should use {\em recursion} to print the list
in reverse order (the order in which they were read).
The {\tt insert} function should
insert successive words into the list pointed to by {\tt p}.
(I assume that {\tt insert} puts each new 
node at the head of the list.  Hints about {\tt insert} are included below.)

{\footnotesize
\begin{verbatim}
      #include <stdio.h>
      #include <stdlib.h>
      #include <string.h>
      struct lnode {
         char *word;
         struct lnode *next;
      };
      struct lnode *insert(char *w, struct lnode *p);
      void printlist(struct lnode *p);
      void printreverse(struct lnode *p);

      void main(void)
      {
         struct lnode *p = NULL;
         char w[100];
         while (scanf("%s", w) != EOF)
            p = insert(w, p);
         printlist(p);
         printreverse(p);
         printf("\n");
      }
 
      void printlist(struct lnode *p)
      {
         /* code for printlist here */
         printf("\n");
      }



      void printreverse (struct lnode *p)
      {
         /* code for printreverse here (no loops) */
      }
      struct lnode *insert(char *w, struct lnode *p)
      {
         struct lnode *r;
         /* Set r = malloced storage for an lnode.                 */
         /* Set r -> word = malloced storage for the input string. */
         /* Copy the input string into the new storage.            */
         /* Give r -> next the proper value.                       */
         /* Return the proper pointer.                             */
      }
      runner% cc -o exam2_2 exam2_2.c
      runner% exam2_3
      Now is the time for   (ctrl-d entered to simulate EOF)
      for time the is Now   (printed by printlist)
      Now is the time for   (printed by printrecurse)
\end{verbatim}
}

\item Consider the following C program, with parts omitted:

{\footnotesize
\begin{verbatim}
      /* Weeks program */
      #include <stdio.h>

      void main(void)
      {
         int i;
         char *weeks[] = {"none", "Mon", "Tue",
            "Wed", "Thu", "Fri", "Sat", "Sun", NULL};
         char **p;
         for(i = 1; i < 8; i++)
            printf("%s  ", /* PART (a) */);
         printf("\n");
         for(i = 1; i < 8; i++)
            printf("%s  ", /* PART (b) */);
         printf("\n");
         p =  /* PART (c) */;
         while ( /* PART (d) */)
            printf("%s  ",  /* PART (e) */);
         printf("\n");
      }
      runner% exam2_3
      Mon  Tue  Wed  Thu  Fri  Sat  Sun    (repeat line twice more)
\end{verbatim}
}

\begin{enumerate}
\item  Supply an expression involving weeks and {\tt []}
 that will print correctly.
\item  Supply an expression involving weeks {\em without} {\tt []}
 that will print correctly.
\item  Supply an expression involving {\tt p} that will position the pointer
to skip the first entry.
\item  Supply an expression involving {\tt p} that will terminate with the
{\tt NULL} at the array's end.
\item  Supply an expression involving {\tt p} that will print correctly.
(Notice that you must 
change {\tt p} here; the variable {\tt i} is not part of this loop.)

\end{enumerate}

\end{enumerate}



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\label{'thatsall'}
\end{document}