Deleting a structure

So i have this structure:

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struct contrib {int num; string name; string adress;};
typedef contrib *cont;

and i was wondering how do i free all the memory that one object of this type ocupies. Does this work:

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void erasecont (cont ct){
    delete[] ct;
}

does it only delete the pointer or it also deletes the int and the strings?

thank you

Lynx876 (742)

If I'm right in saying this, you haven't used the new keyword. So there's nothing to delete.

If you create and 'object' of this struct within a function, then the memory will be freed when it goes out of scope. i.e. the function it was created in ends.

Peter7 (13)

Right, i have this function to create a cont:

cont createcont ()
{cont rcont = new contrib;
string n;

cout << "Name: ";
getline (cin,rcont->name);
cout << "\nNumber: ";
getline (cin, n);
stringstream(n) >> rcont->num;
cout << "\nAdress: ";
getline (cin,rcont->adress);
return rcont;}

so the new is used. and i want the function erasecont to delete everything that was created by this function (i hope i am explaining myself well, i just want to free memory).

Lynx876 (742)

Again, I'm not to sure. But the following compiles and runs for me.
Sorry, I usually deal with deleting 'new' within the same functions!

int *testFunc()
{
	int *me = new int;

	*me = 5;

	return me;
}

void eraseMe( int *value )
{
	delete value;
}

int main()
{
	int *meCopy = testFunc();    

	eraseMe( meCopy );     

	return 0;
}

Hopefully someone with more knowledge will see this thread, lol.
I'd also like to know if this is actually deleting the memory taken by 'new' in the above function.

nedo (83)

delete[] is usually used for deleating arrays. For single objects only use delete.
You create your item as cont rcont = new contrib
if you would create it using cont rcont = new contrib[x]; then you would use delete[];

For example:

#include <iostream>

using namespace std;

struct contrib {int num; string name; string adress;};


int main()
{
  contrib *pCon = new contrib[5];
  contrib *pCon2 = new contrib; 
  delete[] pCon;
  delete pCon2;

  return 0;
}

Peter7 (13)

so that would delete the pointer *pCon2 and get rid of it's num, name and adress?

nedo (83)

Yes, they are considered as just one single object by the compiler.

Peter7 (13)

Thank you for the help!

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Deleting a structure