#ifndef POINTER$\_$H

#define POINTER$\_$H

#include

#include

#include

$//$

$//$ Structure definitions and function pointer typedefs

$//$

typedef double $(*$area$\_$fn$)($void$*$ shape$)$; $//$ Function pointer type

for area functions

typedef double $(*$perimeter$\_$fn$)($void$*$ shape$)$; $//$ Function pointer

type for perimeter functions

typedef struct $\{$

struct $\{$

area$\_$fn area; $//$ Area function for shape

perimeter$\_$fn perimeter; $//$ Perimeter function for shape

$\}$ virtual$\_$func$\_$table; $//$ Table of function pointers for the

emulated virtual functions

const char$*$ name; $//$ Name of shape

unsigned int edges; $//$ Number of edges

$\}$ shape$\_$t; $//$ Generic base class for a shape

typedef struct $\{$

shape$\_$t shape; $//$ Include the base class at the start of a

specific type of shape

double width;

double length;

$\}$ rectangle$\_$t;

typedef struct $\{$

shape$\_$t shape; $//$ Include the base class at the start of a

specific type of shape

double length; $//$ Length of equilateral triangle edge

$\}$ triangle$\_$t;

$//$ Function pointer type for shape comparison functions

$//$ Returns $-1$ if shape$1$ is less than shape$2$

$//$ Returns $1$ if shape$1$ is greater than shape$2$

$//$ Returns $0$ if shape$1$ is equal to shape$2$

typedef int $(*$compare$\_$fn$)($shape$\_$t$*$ shape$1,$ shape$\_$t$*$ shape$2)$;

typedef struct linked$\_$list$\_$node $\{$

shape$\_$t$*$ shape; $//$ Shape associated with the node

struct linked$\_$list$\_$node$*$ next;

$\}$ linked$\_$list$\_$node$\_$t;

typedef struct $\{$

compare$\_$fn compare; $//$ Shape comparison function

linked$\_$list$\_$node$\_$t$*$ head;

$\}$ linked$\_$list$\_$t;

typedef struct tree$\_$node $\{$

shape$\_$t$*$ shape; $//$ Shape associated with the node

struct tree$\_$node$*$ left; $//$ Left subtree

struct tree$\_$node$*$ right; $//$ Right subtree

$\}$ tree$\_$node$\_$t;

#define MAX$\_$DEPTH $30$

typedef struct $\{$

tree$\_$node$\_$t$*$ curr; $//$ Pointer to the current node

unsigned int depth; $//$ Current depth in the tree $($root is at

depth $0)$

tree$\_$node$\_$t$*$ parents$[$MAX$\_$DEPTH$]$; $//$ Pointer to parent nodes

$\}$ tree$\_$iterator$\_$t; $//$ Helper struct for iterating through a tree

$--$ represents a current location within the tree

typedef double $(*$foreach$\_$fn$)($shape$\_$t$*$ shape, double data$)$; $//$

Function pointer type for functions being run foreach shape in a

linked list

$//$

$//$ Shape functions

$//$

$//$ Returns the area of a shape

static inline double shape$\_$area$($shape$\_$t$*$ shape$)$

$\{$

return shape$->$virtual$\_$func$\_$table.area$($shape$)$;

$\}$

$//$ Returns the perimeter of a shape

static inline double shape$\_$perimeter$($shape$\_$t$*$ shape$)$

$\{$

return shape$->$virtual$\_$func$\_$table.perimeter$($shape$)$;

$\}$

$//$ Returns the name of a shape

static inline const char$*$ shape$\_$name$($shape$\_$t$*$ shape$)$

$\{$

return shape$->$name;

$\}$

$//$ Returns the number of edges in a shape

static inline unsigned int shape$\_$edges$($shape$\_$t$*$ shape$)$

$\{$

return shape$->$edges;

$\}$

$//$ Prints info about a shape

static inline void shape$\_$print$($shape$\_$t$*$ shape$)$

$\{$

printf$("\%$s: area $=\%\mathrm{.}2$f$,$ perimeter $=\%\mathrm{.}2$f$,$ edges $=\%$d

$",$

shape$\_$name$($shape$),$ shape$\_$area$($shape$),$ shape$\_$perimeter$($shape$),$

shape$\_$edges$($shape$))$;

$\}$

double rectangle$\_$area$($void$*$ shape$)$;

double triangle$\_$area$($void$*$ shape$)$;

double rectangle$\_$perimeter$($void$*$ shape$)$;

double triangle$\_$perimeter$($void$*$ shape$)$;

void rectangle$\_$construct$($rectangle$\_$t$*$ shape, const char$*$ name,

double width, double length$)$;

void triangle$\_$construct$($triangle$\_$t$*$ shape, const char$*$ name,

double length$)$;

int compare$\_$by$\_$area$($shape$\_$t$*$ shape$1,$ shape$\_$t$*$ shape$2)$;

int compare$\_$by$\_$perimeter$($shape$\_$t$*$ shape$1,$ shape$\_$t$*$ shape$2)$;

$//$

$//$ Linked list functions

$//$

void linked$\_$list$\_$init$($linked$\_$list$\_$t$*$ list, compare$\_$fn compare$)$;

void linked$\_$list$\_$insert$($linked$\_$list$\_$t$*$ list, linked$\_$list$\_$node$\_$t$*$

node$)$;

void linked$\_$list$\_$remove$($linked$\_$list$\_$t$*$ list, shape$\_$t$*$ shape$)$;

$//$

$//$ Tree iterator functions

$//$

void tree$\_$iterator$\_$begin$($tree$\_$iterator$\_$t$*$ iter, tree$\_$node$\_$t$*$

root$)$;

void tree$\_$iterator$\_$next$($tree$\_$iterator$\_$t$*$ iter$)$;

bool tree$\_$iterator$\_$at$\_$end$($tree$\_$iterator$\_$t$*$ iter$)$;

tree$\_$node$\_$t$*$ tree$\_$iterator$\_$get$\_$node$($tree$\_$iterator$\_$t$*$ iter$)$;

shape$\_$t$*$ tree$\_$iterator$\_$get$\_$shape$($tree$\_$iterator$\_$t$*$ iter$)$;

$//$

$//$ Tree analysis functions

$//$

void max$\_$min$\_$avg$\_$area$($tree$\_$node$\_$t$*$ root, double$*$ max, double$*$

min, double$*$ avg$)$;

double foreach$($tree$\_$node$\_$t$*$ root, foreach$\_$fn func, double data$)$;

#endif $//$ POINTER$\_$H