Random generating a array of enum with no repeat elements

[ZhuZhu]

I am trying to generate a array of enum with no same elements, but what I have done still gives me repeat elements. What is wrong with my codes?

P.S I haven't learnt vectors yet thus am not allowed to use it.

const int MAXNO = 7;
const int MAX = 10;

typedef void* VoidPtr;

enum Fruit {Durian, Papaya, Apple, Orange, Mango, Jackfruit, Berry};

void constructVPArray (VoidPtr *, int);
void printVPArray (VoidPtr*, int);

VoidPtr getAFruitVP ();

Fruit getVP (VoidPtr);

char * getFruitStr (Fruit);

bool isDuplicate(VoidPtr, int size, VoidPtr);


int main ()
{
	srand (time (NULL));
	
	VoidPtr* vpArray;
	
	int size = rand () % 7;
	
	cout << "size: " <<size << endl;
	
	vpArray = new VoidPtr [size];
	
	constructVPArray (vpArray, size); 
	printVPArray (vpArray, size);	 	 

}

VoidPtr getAFruitVP ()
{
	int k = rand () % MAXNO;
	Fruit f = static_cast <Fruit>(k);
	
	Fruit *fruitPtr;
	fruitPtr = new Fruit;
	*fruitPtr = f;
	
	VoidPtr vp = fruitPtr;
	
	return vp;
}


void constructVPArray (VoidPtr *vpArray, int size)
{
	VoidPtr *p = &vpArray [0];
	VoidPtr *q = &vpArray [0];
	
	for (int i = 0; i < size; i++)
	{
		*p = getAFruitVP ();
		
		do
		{
			*p = getAFruitVP ();
			
		}while (isDuplicate(*q, i, *p));
		/*
		while (isDuplicate(*q, i, *p))
		{
			*p = getAFruitVP ();	
		} 
		*/	
		++p;
	}
}


void printVPArray (VoidPtr *vpArray, int size)
{
	Fruit f;
	
	VoidPtr *p = &vpArray [0];
	
	for (int i = 0; i < size; i++)
	{
		f = getVP (*p);
	
		cout << f << " --- " << getFruitStr (f) << endl;
		
		++p;
	}
}	 	 

Fruit getVP (VoidPtr vp)
{
	Fruit *fPtr = static_cast <Fruit *>(vp);
	Fruit f = *fPtr;
	
	return f;
}

char * getFruitStr (Fruit f)
{
	char fruitStr [][MAX] = {"Durian", "Papaya", "Apple", "Orange", "Mango", "Jackfruit", "Berry"};
	
	int k = static_cast <int> (f);
	
	char *str = new char [MAX];
	strcpy (str, fruitStr [k]);
	
	return str;
}

bool isDuplicate(VoidPtr q, int size, VoidPtr p)
{				
    for(int j = 0; j < size; j++)
	{
        if (q == p) 
			return true;
		else
			++q;
    }
    return false;
}

[jonnin]

eh. without vectors or shuffle... you are doing way too much work here :)

you can do something like this.

int earray[size];
//fill it in with your values here of course.

for(int i = 0; i < size*2; i++)
{
swap(earray[rand()%size], earray[rand()%size]); //you have to write swap.
}

[jonnin]

this is totally unrelated but watch and learn:

enum Fruit {Durian, Papaya, Apple, Orange, Mango, Jackfruit, Berry, max_Fruit};

now you can do this:

for(int i = Durian, i < max_Fruit, i++)
and the loop still works if you do this later:

enum Fruit {Durian, Papaya, Apple, Orange, Mango, Jackfruit, Berry, Grape, Pineapple, max_Fruit};

as would an array of them:

Fruit x[max_Fruit];

etc. Everything adjusts automatically when you insert more enums if you uses a max on them.

[kbw]

You seem to missing a few basics, pointers and arrays.
https://computer.howstuffworks.com/c22.htm
https://computer.howstuffworks.com/c34.htm