Two different pointer arrays, but they both point to the same address - c++

Question

I'm making a blackjack game and I have a pointer arrays for my dealer's and player's hand. The issue is that when I randomly generate cards to be stored in the array, they both have the same cards. Not sure if it is because they both point to the same address or something I haven't noticed.
#include <iostream>
#include <ctime>
#include <random>
#include <iomanip>
#include <cstdlib>
using namespace std;
class Blackjack
{
public:
Blackjack();
void playGame();
int pbalance;
int betamount;
int loop= 1;
int *playerbalances;
int pbalan,pbal;
void firstbalance();
void clearhand();
private:
int dhandSize;
int phandSize;
int dhandSum;
int phandSum;
int phit;
int pstand;
bool playerDone;
bool dealerDone;
void addPlayerCard();
void addDealerCard();
void printHand();
void sumHands();
void playerbalance();
void playerbet();
int *dhand[];
int *phand[];
};
Blackjack::Blackjack()
{
srand(time(0));
dhandSize = 0;
phandSize = 0;
dhandSum = 0;
phandSum = 0;
playerDone = false;
dealerDone = false;
}
void Blackjack::playGame()
{
if (pbal>0)
{
// Start the player and dealer with two cards
playerbet();
addPlayerCard();
addPlayerCard();
addDealerCard();
addDealerCard();
sumHands();
printHand();
if (dhandSum == 21)
{
cout << "Dealer has blackjack. Dealer wins.\n";
clearhand();
return;
}
else if (phandSum == 21)
{
cout << "Player has blackjack. Player wins.\n";
clearhand();
return;
}
while (dealerDone == false || playerDone == false)
{
if (playerDone == false)
{
cout << "Would you like to hit? (1 - Yes, 2 - No)\n";
cin >> phit;
if (phit == 1)
{
addPlayerCard();
printHand();
sumHands();
if (phandSum > 21)
{
cout << "Player's hand exceeded 21. Player loses"<<endl;
pbalan =(pbalan - betamount);
cout <<"[you lose $"<<betamount<<" of money!]"<<endl;
cout <<"[your current balance is: $"<<pbalan<<"]"<<endl;
clearhand();
return;
}
}
}
if (playerDone == false)
{
cout << "Would you like to stand? (1 - Yes, 2 - No)\n";
cin >> pstand;
}
if (pstand == 1)
{
playerDone = true;
}
if (dhandSum < 17 && dealerDone != true)
{
addDealerCard();
printHand();
sumHands();
if (dhandSum > 21)
{
cout << "Dealer hand exceeded 21. Dealer loses.\n";
return;
}
}
else if (dhandSum >= 17)
{
dealerDone = true;
}
if (phandSum == 21 && dhandSum == 21)
{
cout << "Push, player and dealer reached 21.\n";
return;
}
else if (phandSum == 21)
{
cout << "Player reached 21. Player wins.\n";
return;
}
else if (dhandSum == 21)
{
cout << "Dealer reached 21. Dealer wins.\n";
pbalan =(pbalan - betamount);
cout <<"[you lose $"<<betamount<<" of money!]"<<endl;
cout <<"[your current balance is: $"<<pbalan<<"]"<<endl;
return;
}
if ((playerDone == true && dealerDone == true) || (phandSize == 5 && phandSize == 5))
{
if (dhandSum < phandSum)
{
cout << "Sum of your hand exceeds the dealer's sum of " << dhandSum << "! You win!";
return;
}
else if (phandSum == dhandSum)
{
cout << "Dealer sum of " << dhandSum << " is equal to the sum of your hand. Tie game.";
return;
}
else if (dhandSum > phandSum)
{
cout << "Sum of your hand is lower than the dealer's sum of " << dhandSum << ". You lose!"<<endl;
pbalan =(pbalan - betamount);
cout <<"[you lose $"<<betamount<<" of money!]"<<endl;
cout <<"[your current balance is: $"<<pbalan<<"]"<<endl;
return;
}
}
}
}
}
void Blackjack::clearhand()
{
for (int i = 0; i < dhandSize; i++) { delete dhand[i]; }
for (int i = 0; i < phandSize; i++) { delete phand[i]; }
phandSize = 0;
dhandSize = 0;
}
void Blackjack::firstbalance()
{
cout << "Welcome to Blackjack" <<endl;
cout << "please enter a starting balance: " <<endl;
cin >> pbal;
playerbalances = &pbalan;
*playerbalances = pbal;
}
void Blackjack::playerbet()
{
cout << "how much do you want to bet?"<<endl;
cin >> betamount;
}
void Blackjack::addPlayerCard()
{
if (phandSize <= 5)
{
*phand[phandSize] = 1 + (rand() % 13);
phandSize++;
}
else
{
cout << "Sorry. You have reached the maximum number of cards (5)." << endl;
playerDone = true;
}
}
void Blackjack::addDealerCard()
{
if (dhandSize <= 5)
{
*dhand[dhandSize] = 1 + (rand() % 13);
dhandSize++;
}
else
{
dealerDone = true;
}
}
void Blackjack::printHand()
{
cout << "Your current hand is...\n";
for (int i = 0; i < phandSize; i++)
{
cout << " -" << *phand[i] << "- \n\n";
}
cout << "Dealer's current hand is...\n";
for (int j = 0; j < dhandSize; j++)
{
cout << " -" << *dhand[j] << "- \n\n";
}
}
void Blackjack::sumHands()
{
dhandSum = 0;
phandSum = 0;
for (int i = 0; i < dhandSize; i++)
{
dhandSum += *dhand[i];
}
for (int j = 0; j < phandSize; j++)
{
phandSum += *phand[j];
}
cout << "Current player hand sum is: " << phandSum << endl;
}
using namespace std;
int main()
{
int exitGame = 1;
int i = 0;
Blackjack play;
if (i<1)
{
play.firstbalance();
i++;
}
do
{
play.playGame();
play.clearhand();
cout << "\nWould you like to play again? (1 - Yes, 2 - No)\n";
cin >> exitGame;
}
while (exitGame == 1);
cout << "\nThanks for playing!\n";
return 0;
}
The dealer cards should be different from the player cards but they are identical when you run the program.

Answer 1

The shows code declares a class with two members, as follows:
int *dhand[];
int *phand[];
These are the two members of the class, but this is not valid, standard C++. Variable-length arrays are not standard C++.
As such, the entire logic in this code becomes unspecified behavior. The behavior you observed was that the two arrays appear to be the same. Right. That's what unspecified behavior means, and this appears to be the behavior that results with your specific C++ compiler and implementation. Your C++ compiler appears to implement this by creating a class member whose size is a grand total of 0 bytes (after all, the size of the array is not specified, so it's nuthin'), with the expectation that this will be the last class member, and the application will be responsible for allocating some extra memory in addition to the one that's required for an instance of this object, in order to achieve a pseudo-array in this fashion.
But with two class members declares thusly, this ends up with two class members that are effectively one and the same. Which is the behavior you observed. Other C++ compilers may very well report a compilation error, since the program being ill-formed, with respect to the C++ standard.
To fix this issue you should replace these class members with proper arrays. Perusing the shown code, it looks like you expect these arrays to be, essentially, variably-sized arrays. This is what std::vector is for, and your C++ book should have one or more chapters that fully explain how to use std::vector to implement an array-like object that can grow and shrink in size, accordingly.