How to call multiple classes in C++ - c++

Question

Here is the code I'm trying to create, and yes its messy for now. To give some back story I'm trying to figure out how to call a class multiple times without doing it seperately. What I mean is instead of performing:
Dice diceOne;
Dice diceTwo; and so on, I want to know if it is possible to just put it as Dice dicewhatever(*) and have that be a modifiable variable. This is so that I can set that variable to a number and then decrement it based on a score.
I dont know if this is even possible, but at this point I've beat my head against this so much I'm just pulling at straws to see if it would be a fit.
class Dice {
public:
Dice();
int Roll();
int currentDiceSide();
private:
int diceRoll;
int diceReRoll; //Declares and initializes the number of dice to allow for roll next dice throw.
};
Dice::Dice()
: //This is the beginning of the class and sets diceRoll to zero
diceRoll(0)
{
}
int Dice::Roll()
{ //This function actually does the random roll within the class Dice.
diceRoll = ((rand() % 6) + 1);
return diceRoll;
}
int Dice::currentDiceSide()
{ //This function returns the value of the dice roll for the class call.
return diceRoll;
}
void Game::Rules()
{
ifstream inFile;
inFile.open("Farkle Rules.txt");
string line;
if (inFile.fail()) {
cerr << "Error opening file" << endl;
exit(1);
}
if (inFile.is_open()) {
while (inFile.good()) {
getline(inFile, line);
cout << line << endl;
}
inFile.close();
}
}
void Game::GetPlayerInput(int playerInput)
{
cin >> playerInput;
}
void Game::RunGame()
{
Rules();
bool farkle = false;
double turnSum = 0;
double value = 0;
int i = 0;
int w = 6;
int players = 0;
int numPlayer = 0;
int diceOneValue = 0;
int diceTwoValue = 0;
int diceThreeValue = 0;
int diceFourValue = 0;
int diceFiveValue = 0;
int diceSixValue = 0;
int num1s = 0; //Declaring and initializing the variables to hold how many times a number shows up in a roll.
int num2s = 0;
int num3s = 0;
int num4s = 0;
int num5s = 0;
int num6s = 0; //
srand(static_cast<unsigned int>(time(0)));
cout << "Welcome to Farkle!" << endl
<< endl;
cout << "Please enter the number of players " << endl;
cin >> players;
//Dice diceOne;
//diceOne.currentDiceSide();
//Dice diceTwo;
//diceTwo.currentDiceSide();
//Dice diceThree;
//diceThree.currentDiceSide();
//Dice diceFour;
//diceFour.currentDiceSide();
//Dice diceFive;
//diceFive.currentDiceSide();
//Dice diceSix;
//diceSix.currentDiceSide();
Dice diceOne(w);
< -this is the line that I would like to create with a variable that is modifiable.

Answer 1

You cannot give each Dice object a name, but you can create a Vector of Dice object pointers (vectors are basically resizable arrays), like this:
#include <vector>
#include <iostream>
//...
std::cout << "Please enter the number of players " << std::endl;
std::cin >> players;
// do something to make sure players is an integer
// initialize the empty playerDice vector
std::vector<Dice*> playerDice = {};
for (unsigned i = 0; i < players; ++i) {
playerDice.push_back(new Dice); // this adds a new Dice object pointer to the end of the vector
playerDice.at(i)->currentDiceSide();
}
You have then called the currentDiceSide() function on each Dice object you created, and have neatly organized them in a Vector, which you can access like this:
// say we want to access the third Dice Object,
// Vectors start counting at 0, so we acces the element at Index 2.
playerDice.at(2)->doSomething();
Now because you instantiated those Dice objects with new you have to remember to delete them when you're finished with them, otherwise this will create a memory leak.
//...
// this deletes all the Dice objects in the vector, and points the remaining pointers to null
for (auto d : playerDice) {
delete d;
d = nullptr;
}
Or, better yet, if you're using C++11, you can use std::unique_ptr instead of the raw C-style pointers. Those will prevent you from creating memory leaks, because they will be deleted when they go out of scope. Note you have to #include <memory> to use these.
The vector definition then turns into:
std::vector< std::unique_ptr<Dice> > playerDice = {};
And the creation of the objects would look like this
for (unsigned i = 0; i < players; ++i) {
Dice* temp = new Dice;
temp->currentDiceSide();
std::unique_ptr<Dice> uPtr{ temp };
playerDice.push_back(std::move(uPtr));
}
You can then just clear the vector when you're done with all the objects:
playerDice.clear();
which will delete all the Dice objects that you put into the vector.