Polymorphism in an Adventure Game (Room and Thing unchanged so not included)

Item.cpp

#include "Item.h"
#include <iostream>

Item::Item()
	: Thing()
	, useable(false)
{
}

Item::Item(string newName, string newDesc, bool newUseable)
	: Thing(newName, newDesc)
	, useable(newUseable)
{
}

Item::~Item()
{
}

void Item::Print()
{
	Thing::Print();
	if (useable)
	{
		cout << " This item can be used.";
	}
}

bool Item::IsUseable()
{
	return useable;
}

void Item::UseItem(int& playerStamina)
{
	cout << "You use the " << name << "." << endl;
}

Item.h

#pragma once
#include "Thing.h"

class Item :
    public Thing
{
private:
    bool useable;

public:
    Item();
    Item(string newName, string newDesc, bool newUseable);
    ~Item();

    void Print();
    bool IsUseable();
    virtual void UseItem(int& playerStamina);
};

Main.cpp

// Libraries
#include <string>
#include <iostream>
#include <vector>
#include "Room.h"
#include "Item.h"
#include "Potion.h"

// Needed to avoid having to type std:: a lot!
using namespace std;

void TempFuncRoomDestructorTest(Room* existingRoom)
{
	Room tempRoom("TempName", "TempDesc");
	tempRoom.AddExit(existingRoom);
	existingRoom->AddExit(&tempRoom);
}


// Function to Move the player to a different room
void Move(Room * &currentRoom, int& stamina)
{
	// Print out the room the player is in
	cout << "You are in the ";
	currentRoom->Print();

	// INITIALISE a local bool vairable called processInput, to true
	bool processInput = true;
	// WHILE processInput is true...
	while (processInput)
	{
		// INITIALISE a local playerChoice variable
		int playerChoice = 0;

		// DISPLAY the player's current stamina
		cout << "Stamina remaining: " << stamina << endl;

		// DISPLAY the player's current stamina
		cout << "Where would you like to go? (enter the number)" << endl;

		// READ the player's response into the playerChoice variable
		cin >> playerChoice;

		// IF the player's choice between 1 and the roomNames vector size...
		if (playerChoice >= 1 && playerChoice <= currentRoom->GetNumExits())
		{
			currentRoom = currentRoom->GetExit(playerChoice-1);
			processInput = false;
		}
		// ELSE 
		else
		{
			// DISPLAY an error message due to unrecognised input
			cout << "Sorry, the number you typed was not one of the options: " << playerChoice << endl;

			// CLEAR the input stream
			cin.clear();
			cin.ignore(numeric_limits<streamsize>::max(), '\n');
		} // END IF
	} // ENDWHILE
}

// Function to Pick up an item and add it to the backpack
void PickUp(Room* currentRoom, vector<Item*>& backpack)
{
	// Print out the room the player is in
	cout << "You are in the ";
	currentRoom->Print();

	// EXIT if there are no items
	if (currentRoom->GetNumItems() == 0)
	{
		cout << "There are no items in this room." << endl;
		return;
	}

	// INITIALISE a local bool vairable called processInput, to true
	bool processInput = true;
	// WHILE processInput is true...
	while (processInput)
	{
		// INITIALISE a local playerChoice variable
		int playerChoice = 0;

		// DISPLAY the player's current stamina
		cout << "What item would you like to take? (enter the number)" << endl;

		// READ the player's response into the playerChoice variable
		cin >> playerChoice;

		// IF the player's choice between 1 and the roomNames vector size...
		if (playerChoice >= 1 && playerChoice <= currentRoom->GetNumItems())
		{
			cout << "You take the " << currentRoom->GetItem(playerChoice - 1)->GetName() << " and put it in your backpack." << endl;

			backpack.push_back(currentRoom->GetItem(playerChoice - 1));
			currentRoom->RemoveItem(playerChoice - 1);
			processInput = false;
		}
		// ELSE 
		else
		{
			// DISPLAY an error message due to unrecognised input
			cout << "Sorry, the number you typed was not one of the options: " << playerChoice << endl;

			// CLEAR the input stream
			cin.clear();
			cin.ignore(numeric_limits<streamsize>::max(), '\n');
		} // END IF
	} // ENDWHILE
}

// Function to use an item from the backpack
void UseItem(vector<Item*>& backpack, int & playerStamina)
{
	if (backpack.size() == 0)
	{
		cout << "You currently have nothing in your backpack, so you cannot use an item." << endl;
		return;
	}

	// Print out the contents of the backpack
	cout << "Your backpack holds the following:" << endl;

	// FOR each item in the items vector...
	for (unsigned int i = 0; i < backpack.size(); ++i)
	{
		// DISPLAY the loop index + 1 and the name of the item at that index
		cout << (i + 1) << ".   " << backpack[i]->GetName() << endl;
	}
	// END FOR

	// INITIALISE a local bool vairable called processInput, to true
	bool processInput = true;
	// WHILE processInput is true...
	while (processInput)
	{
		// INITIALISE a local playerChoice variable
		int playerChoice = 0;

		// DISPLAY the player's current stamina
		cout << "What item would you like to use? (enter the number)" << endl;

		// READ the player's response into the playerChoice variable
		cin >> playerChoice;

		// IF the player's choice between 1 and the roomNames vector size...
		if (playerChoice >= 1 && playerChoice <= backpack.size())
		{
			if (backpack[playerChoice - 1]->IsUseable())
			{
				backpack[playerChoice - 1]->UseItem(playerStamina);
				backpack.erase(next(backpack.begin(), playerChoice - 1));
			}
			else
			{
				cout << "The " << backpack[playerChoice - 1]->GetName() << " cannot be used." << endl;
			}
			processInput = false;
		}
		// ELSE 
		else
		{
			// DISPLAY an error message due to unrecognised input
			cout << "Sorry, the number you typed was not one of the options: " << playerChoice << endl;

			// CLEAR the input stream
			cin.clear();
			cin.ignore(numeric_limits<streamsize>::max(), '\n');
		} // END IF
	} // ENDWHILE
}

// Main function where program code execution begins and ends.
int main()
{
	// INITIALISE variables
	string playerName = "";
	int playerChoice = -1;
	int moveCost = 5;
	int playerStamina = 20;
	bool exit = false;
	vector<Item*> backpack;

	// Create rooms
	Room courtyard("Courtyard", "A barren, weed-filled courtyard of a crumbling ruined castle.");

	Room entryHall("Entry Hall", "A once-grand hll with a rotting red carpet, lined with rusted suits of armour.");

	Room gate("Gate", "The dilapidated gates hang crookedly from their hinges, set into the crumbling stone wall that surrounds the ruined castle.");

	courtyard.AddExit(&entryHall);
	courtyard.AddExit(&gate);

	gate.AddExit(&courtyard);

	entryHall.AddExit(&courtyard);

	Room * currentRoom = &courtyard;

	// TEST our room destructor. If successful, we should not have a connection to the temp room as it will delete itself
	TempFuncRoomDestructorTest(&courtyard);

	// CREATE items
	Item hat("Hat", "A battered old hat.", false);
	Potion potion("Potion", "A mysterious blue potion.", 10);
	Item coin("Coin", "A tarnished old copper coin.", false);

	// ADD the items to rooms
	courtyard.AddItem(&potion);
	courtyard.AddItem(&coin);
	gate.AddItem(&hat);

	// DISPLAY the title of the program.
	cout << "Welcome to the Example Adventure Game!" << endl;

	// DISPLAY a message to the player asking their name.
	cout << "What are you called, brave adventurer?" << endl;

	// READ the player's response into the playerName variable
	getline(cin, playerName);
	cout << endl;

	// DISPLAY a greeting to the player, using the playerName variable
	cout << "Welcome, " << playerName << ", soon to be hero of the realm!" << endl << endl;

	// WHILE exit is false...
	while (!exit)
	{
		cout << "You are in the " << currentRoom->GetName() << endl;

		cout << "What would you like to do? Enter the number for your choice." << endl;
		cout << "1. Move" << endl;
		cout << "2. Pick Up Item" << endl;
		cout << "3. Use Item" << endl;
		cout << "4. Quit" << endl;

		// Initialise player choice
		playerChoice = -1;

		// READ the player's response into the playerChoice variable
		cin >> playerChoice;


		if (playerChoice == 1)
		{
			// Move!
			Move(currentRoom, playerStamina);

			// SUBTRACT the stamina required to move from the player's stamina value
			playerStamina = playerStamina - moveCost;

			// DISPLAY a message that the player has moved and used moveCost stamina
			cout << "You have changed rooms and used " << moveCost << " stamina." << endl;

			// IF the player stamina reaches 0 or lower...
			if (playerStamina <= 0)
			{
				// DISPLAY a message to the player telling them they have died
				cout << "You have run out of stamina and died! Better luck next time. Please play again!" << endl;

				// SET exit to true
				exit = true;
			}
			// ENDIF
		}
		else if (playerChoice == 2)
		{
			// Pick Up Item!
			PickUp(currentRoom, backpack);
		}
		else if (playerChoice == 3)
		{
			// Use Item!
			UseItem(backpack, playerStamina);
		}
		else if (playerChoice == 4)
		{
			// Quit!
			
			// DISPLAY a goodbye message to the player
			cout << "Thank you for playing!" << endl;

			// SET exit to true
			exit = true;
		}
		// ELSE 
		else
		{
			// DISPLAY an error message due to unrecognised input
			cout << "Sorry, the number you typed was not one of the options: " << playerChoice << endl;

			// CLEAR the input stream
			cin.clear();
			cin.ignore(numeric_limits<streamsize>::max(), '\n');
		} // END IF


	}
	// END WHILE

}

Potion.cpp

#include "Potion.h"
#include <iostream>

Potion::Potion()
	: Item		()
	, toHeal	(0)
{
}

Potion::Potion(string newName, string newDesc, int newToHeal)
	: Item		(newName, newDesc, true)
	, toHeal	(newToHeal)
{
}

Potion::~Potion()
{
}

void Potion::UseItem(int& playerStamina)
{
	cout << "You use the " << name << " and recover "<< toHeal <<" stamina." << endl;
	playerStamina = playerStamina + toHeal;
}

Potion.h

#pragma once
#include "Item.h"
class Potion :
    public Item
{
private:
    int toHeal;

public:
    Potion();
    Potion(string newName, string newDesc, int newToHeal);
    ~Potion();

    void UseItem(int& playerStamina);
};