deleting memory

[Maurader]

If I have a function
struct myStruct{
double myDouble;
}

func(vector <myStruct> &myVector){
myStruct dynamicMyStruct;
dynamicMyStruct = new myStruct;
myVector.push_back(dynamicMyStruct);
}

how do I delete the memory associatted with dynamicMyStruct? I cannot delete it at the end of the function since I still need the contents of the vector after the function returns...

Thanks!

 

[Leibnitz]

you can create a &quot;constructor&quot; and a &quot;destructor&quot; for your structure so then you will allocate memory for &quot;dynamicMyStruct&quot; in your &quot;constructor&quot; and delete back in your &quot;destructor&quot;.

struct myStruct
{
   myStruct(); //constructor
   ~myStruct(); //destructor
   double myDouble;
};

myStruct *dynamicMyStruct;

myStruct::myStruct()
{
   dynamicMyStruct = new myStruct;
}

myStruct::~myStruct()
{
   delete dynamicMyStruct;
}

 

[Maurader]

will the memory be cleared if i said myVector.clear()?

 

[Maurader]

what if it's a built-in type like double/int?

 

[JOLESEN]

I think you have a problem in func() :

You cannot push_back() a pointer on a vector<myStruct> (The vector doesn't hold pointers)

Instead you should push_back(a_myStruct_instance)
You don't need to bother with memory allocation : vector will do that.

If you happen to have a pointer to a myStruct object use push_back(*ptr), and delete ptr afterwards if required.


/JOlesen

 

[JOLESEN]

Vector doesn't need to keep objects sorted, so you won't need it here.

This code compiles fine my computer :

#include <vector>
using namespace std;

struct myStruct{
double myDouble;
};

void func(vector <myStruct> &myVector)
{
myStruct s;
myVector.push_back(s);
}


void main(void)
{
vector<myStruct> vec;

func(vec);
}

/JOlesen