Unable to delete contents of dynamic array in C++ - c++

Question

I've been beating my head against this one for awhile. In the deconstructor of my class, I have a for loop that is supposed to iterate through an array of objects and delete them. When I try though, I get a read access violation. The attached code is supposed to read info from two documents and use that to create Country objects.
#include "pch.h"
#include "CountryCatalogue.h"
#include "Country.h"
#include <iterator>
#include <map>
//imports for reading the files
#include <iostream>
#include <fstream>
CountryCatalogue::CountryCatalogue()
{
_maxSize = 10;
_curSize = 0;
_catalogue = new Country*[_maxSize];
}
CountryCatalogue::CountryCatalogue(std::string continentFileName, std::string countryFileName)
{
//block that opens the files and checks to make sure they can be read
//open up the files
std::ifstream inFile1;
std::ifstream inFile2;
//opening both text files and ensuring that the file is readable to the program
inFile1.open(continentFileName);
if (!inFile1) {
std::cout << "Unable to open file";
exit(1); // terminate with error
}
inFile2.open(countryFileName);
if (!inFile2) {
std::cout << "Unable to open file";
exit(1); // terminate with error
}
// read the continet file
// while there is still stuff to read in the file
std::string str;
while (!inFile1.eof())
{
std::string Country, Cont;
//reading lines from file and assigning to variables
std::getline(inFile1, Country);
std::getline(inFile1, Cont);
//mapping to variables read from file
_countryContinent.insert(std::pair<std::string, std::string>(Country, Cont));
_curSize++;
}
//closing file after use
inFile1.close();
//creating array
_catalogue = new Country*[_curSize+2];
//resetting size to zero for later itteration
_curSize = 0;
// read the country file
// while there is still stuff to read in the file
while (!inFile2.eof())
{
std::string name, POP, AREA;
int pop;
double area = 0.0;
std::getline(inFile2, name);
std::getline(inFile2, POP);
std::getline(inFile2, AREA);
if (!POP.empty() && POP[POP.length() - 1] == '\n') {
POP.erase(POP.length() - 1);
}
if (!AREA.empty() && AREA[AREA.length() - 1] == '\n') {
AREA.erase(AREA.length() - 1);
}
pop = std::stoi(POP);
area = std::stod(AREA);
//creating iterator to search through mapped values
std::map<std::string, std::string>::iterator it;
it = _countryContinent.find(name);
//creating empty string variable to store continent
std::string cont;
//using value found by iterator to make continent string
//ensuring value isn't the end valueof the map
if (it != _countryContinent.end()){
cont = it->second;
}
//std::cout << name << pop << area << cont << std::endl;
// add the country to the catalogue
addCountry(name, pop, area, cont);
}
}
CountryCatalogue::~CountryCatalogue() {
/*for (int i = 0; i < _curSize; i++){
delete _catalogue[i];
std::cout << "deleted" << i << std::endl;
}*/
delete[] _catalogue;
}
void CountryCatalogue::addCountry(std::string name, int pop, double area, std::string cont) {
//std::cout << name << pop << area << cont << std::endl;
//std::cout << _curSize << std::endl;
Country* toAdd = new Country(name, pop, area, cont);
if (_curSize == _maxSize) {
expandCapacity();
}
//adding country object to array
_catalogue[_curSize] = toAdd;
//adding to _curSize for next iteration
_curSize++;
}
void CountryCatalogue::printCountryCatalogue() {
std::string s;
/*for (int i = 0; i < _curSize; i++) {
s += _catalogue[i]->to_string() + "\n";
}*/
std::cout << _curSize << std::endl;
}
void CountryCatalogue::expandCapacity() {
//doubling array size
_maxSize = _maxSize * 2;
//creating pointer to new array of new size
Country** newCatalogue = new Country*[_maxSize];
//copying old array into new
for (int i = 0; i < _curSize; i++) {
newCatalogue[i] = _catalogue[i];
}
//deleting old array
delete[] _catalogue;
//making _catalogue point to newCatalogue
_catalogue = newCatalogue;
}
UPDATE:
What my code is supposed to do is get information from text files and create objects using that data. I am required to use an array instead of a vector. The code runs fine and I can create the country object. The issue is that I cannot add the created object to the _catalogue array, as I cannot delete it afterwards. When I attempt to iterate through the array, I receive a message saying Heap Corruption was detected.

Answer 1

Your problem is due to this line
_catalogue = new Country*[_curSize+2];
in the second constructor. You have forgotten to update _maxSize so you have a mismatch between _maxSize and the real allocated amount of memory.
Try:
_maxSize = _curSize+2;
_catalogue = new Country*[_maxSize];

Answer 2

You created _catalogue as a dynamic array.
To release the memory allocated for arrays of elements using new TYPE[SIZE] the syntax is:
delete[] _catalogue;
Loop is Needed for deleting memory allocated for Matrix elements. For example
int matrix = new int[rows][cols];
for (int i = 0; i < rows; ++i)
delete [] matrix[i];
The array is deleted row by row.