main.cpp

#include

#include

#include

#include "GroceryList.h$"$

using namespace std;

bool ParseIndices$($std::string str$,$ int& outIndex$1,$ int& outIndex$2)$;

int main$($int argc, char $*$argv$[])\{$

$//$ Initialize a new grocery listGroceryList groceryList;string command;bool quit $=$ false;while $(!$quit$)\{$getline$($cin$,$ command$)$;

$//$ Process user input

if $($command $==$ "print"$)\{$

groceryList.Print$($cout$)$;$\}$else if $(0==$ command.find$("$add $"))\{$

groceryList.AddWithUndo$($command$.$substr$(4))$;

$\}$else if $(0==$ command.find$("$removeat $"))\{$int index $=$ stoi$($command$.$substr$(9))$;groceryList.RemoveAtWithUndo$($index$)$; $\}$else if $(0$command.find$("$swap $"))\{$

int index$1=-1,$ index$2=-1$;

if $($ParseIndices$($command$.$substr$(5),$ index$1,$ index$2))\{$ groceryList.SwapWithUndo$($index$1,$ index$2)$;$\}$else $\{$cout $<<"\backslash "$swap$\backslash "$ command requires two indices, separated $"$;cout $<<"$by a space. Ex: swap $25"<<$ endl;$\}\}$else if $($command $==$ "undo"$)\{$if $(0==$ groceryList.GetUndoStackSize$())\{$cout $<<$ "Cannot execute undo because undo stack is empty" $<<$ endl;$\}$else $\{$groceryList$.$ExecuteUndo$()$;$\}\}$else if $($command $==$ "quit"$)\{$quit $=$ true;$\}$else $\{$cout $<<$ "Unknown command: $"<<$ command $<<$ endl;$\}\}$return $0$;$\}$

bool ParseIndices$($std::string str$,$ int& outIndex$1,$ int& outIndex$2)\{$auto spaceIndex $=$ str$.$find$("")$;if $($spaceIndex $==$ string::npos$)\{$return false;$\}$outIndex$1=$ stoi$($str$)$;outIndex$2=$ stoi$($str$.$substr$($spaceIndex $+1))$;return true;$\}$

UndoCommand.h

#ifndef UNDOCOMMAND$\_$H

#define UNDOCOMMAND$\_$H

class UndoCommand $\{$

public:virtual ~UndoCommand$()\{\}$ virtual void Execute$()=0$;$\}$;#endif

RemoveLastCommand.h

#ifndef REMOVELASTCOMMAND$\_$H

#define REMOVELASTCOMMAND$\_$H

#include

#include

#include "UndoCommand.h$"$

class RemoveLastCommand : public UndoCommand $\{$

private:

std::vector$*$ sourceVector;

public:

RemoveLastCommand$($std::vector$*$ vector$)\{$

sourceVector $=$ vector;

$\}$

void Execute$()$ override $\{$

if $(!$sourceVector$->$empty$())\{$

sourceVector$->$pop$\_$back$()$;

$\}\}\}$;

#endif

SwapCommand.h

#ifndef SWAPCOMMAND$\_$H

#define SWAPCOMMAND$\_$H

#include

#include

#include "UndoCommand.h$"$

class SwapCommand : public UndoCommand $\{$

private:$//$ Your member variable declarations herepublic:$/$ Your constructor code herevoid Execute$()$ override $\{//$ Your code here$\}\}$;

#endif

InsertAtCommand.h

#ifndef INSERTATCOMMAND$\_$H

#define INSERTATCOMMAND$\_$H

#include

#include

#include "UndoCommand.h$"$

class InsertAtCommand : public UndoCommand $\{$

private:

$//$ Your member variable declarations here

public:

$//$ Your constructor code here

void Execute$()$ override $\{/$ Your code here$\}\}$;

#endif

GroceryList.h

#ifndef GROCERYLIST$\_$H

#define GROCERYLIST$\_$H

#include

#include

#include "UndoCommand.h$"$

#include "RemoveLastCommand.h$"$

#include "InsertAtCommand.h$"$

#include "SwapCommand.h$"$

class GroceryList $\{$

protected:

std::vector listItems;

std::stack undoStack;

public:

virtual void AddWithUndo$($std::string newItemName$)\{$

$//$ Add the new list item

listItems.push$\_$back$($newItemName$)$;

$//$ Make an undo command that removes the last item and push onto stack

undoStack.push$($new RemoveLastCommand$($&listItems$))$;$\}$

virtual void RemoveAtWithUndo$($int removalIndex$)\{$

$//$ Your code here$\}$

virtual void SwapWithUndo$($int index$1,$ int index$2)\{$

$//$ Your code here

$\}//$ Pops and executes the undo command at the top of the undo stack. Then

$//$ deletes the executed command.

virtual void ExecuteUndo$()\{$

$//$ Your code here $\}$virtual int GetListSize$()$ const $\{$return $($int$)$listItems$.$size$()$;$\}$virtual int GetUndoStackSize$()$ const $\{$

return $($int$)$undoStack$.$size$()$;$\}$virtual std::vector GetVectorCopy$()$ const $\{$ return listItems;$\}$virtual void Print$($std::ostream& outputStream$)\{$for $($size$\_$t i $=0$; i $<$ listItems.size$()$; i$++)\{$outputStream $<<$ i $<<"."<<$ listItems$[$i$]<<$ std::endl;$\}\}\}$;#endif