Inserting new Object to Repository throws error - c++

Question

I've created an object and a Repository for it.
When I try inserting the object into the Repository (with the insert function i've created) I get compile error.
The Class I'm trying to insert into Repository
class Payment{
private:
int day;
int amount;
char *type;
public:
Payment();
Payment(int day, int amount, char *type);
Payment(const Payment &p);
~Payment();
//getters
int getDay()const;
int getAmount()const;
char* getType()const;
//setters
void setDay(int day);
void setAmount(int amount);
void setType(char* type);
//operator
Payment& operator=(const Payment& other);
friend ostream& operator<<(ostream &os,const Payment &obj);
};
//copy constructor
Payment::Payment(const Payment & p){
this->day = p.day;
this->amount = p.amount;
if(this->type!=NULL)
delete[] this->type;
this->type = new char[strlen(p.type)+1];
strcpy_s(this->type, strlen(p.type) + 1, p.type);
}
//assignment operator
Payment& Payment::operator=(const Payment &other) {
this->day = other.day;
this->amount = other.amount;
this->type = new char[strlen(other.type) + 1];
strcpy_s(this->type, strlen(other.type) + 1, other.type);
return *this;
}
//destructor
Payment::~Payment(){
this->day = 0;
this->amount = 0;
if (this->type != NULL) {
delete[]this -> type;
this->type = NULL;
}
}
//Repository header
class Repository{
private:
vector<Payment> list;
public:
Repository();
int getLength();
void insert(const Payment& obj);
void remove(int position);
};
//Repository cpp
Repository::Repository(){
this->list.reserve(10);
}
//return the size of the list
int Repository::getLength() {
return this->list.size();
}
//add payment to list
void Repository::insert(const Payment &obj) {
this->list.emplace_back(obj);
}
//remove payment from list
void Repository::remove(int position) {
this->list.erase(this->list.begin() + position);
}
In main function I have
char c[] = "some characters";
Payment pay = Payment(7,9,c);
Repository rep = Repository();
rep.insert(pay);
When I run the program I get the error "
Expression: _CrtlsValidHeapPointer(block) "

Answer 1

Since std::vector will make copies, a std::vector<Payment> requires that Payment has correct copy semantics. Your copy constructor and assignment operator are not implemented correctly. The assignment operator causes memory leaks, since you failed to delete [] the existing memory.
The easiest solution is to drop using the char *type; member and simply use std::string type;. Then the Payment class would have the correct copy semantics automatically.
Given that, the corrections to your Payment class is below:
#include <algorithm>
//...
Payment::Payment() : day(0), amount(0), type(nullptr) {}
Payment::Payment(const Payment & p) : day(p.day), amount(p.amount), type(nullptr)
{
if ( p.type )
{
type = new char[strlen(p.type) + 1];
strcpy_s(this->type, strlen(p.type) + 1, p.type);
}
}
// Use the copy/swap idiom
Payment& Payment::operator=(const Payment &other)
{
Payment temp(other); // make a temporary copy
// swap out contents of temporary with this object
std::swap(temp.day, day);
std::swap(temp.amount, amount);
std::swap(temp.type, type);
return *this;
} // when this brace has been reached, the temp copy dies off with the old data
Payment::~Payment()
{
delete [] type;
}
The above uses the copy/swap idiom within the assignment operator. The copy constructor uses a member initialization list.
The destructor need not check for a null pointer, since deleting a nullptr is perfectly valid.

Answer 2

Now adding to a std::vector is working well, without any runtime error (using the code #PaulMcKenzie posted). I've also found an example of code that's working, where only the assignment operator is kinda different.
Converted to my code would be (and it's working either):
Payment& Payment::operator=(const Payment &other) {
if (this != &other) {
this->setDay(other.day);
this->setAmount(other.amount);
this->setType(other.type);
}
return *this;
}
Thanks for the help! Now it's working perfectly! I didn't get to study very much from <algorithm> library, so I'll have to take a closer look. Wish you the best luck! ^_^