I am trying to recreate the vector class with its basic functions, but my program keeps exiting halfway through the operations. When I run the debugger it fully executes just fine. Here is what my vector class looks like:
template<class T>
class Vector {
T* _array;
size_t _size;
size_t _capacity;
public:
Vector() : _size(0), _capacity(8), _array(new T[_capacity]) { }
~Vector() { delete[] _array; }
void _grow() {
T* tmp = _array;
size_t old_cap = _capacity;
_capacity *= 2;
_array = new T[_capacity];
for (size_t i = 0; i < old_cap; i++) {
_array[i] = tmp[i];
}
delete[] tmp;
}
void push_back(T const& item) {
if (_size == _capacity) { _grow(); }
_array[_size++] = item;
}
void pop_back() {
_size--;
}
void insert(T item, int position) {
// implement insert here
for (int i = position; i < _size-1; i++) {
_array[i+1] = _array[i];
}
_size++;
if (_size == _capacity) {
_grow();
}
_array[position] = item;
}
void remove(int position) {
// implement remove here
for (int i = position; i < _size-1; i++) {
_array[i] = _array[i+1];
}
_size--;
}
T& operator[](int index) {
// implement operator[] here
return _array[index];
}
size_t size() const {
return _size;
}
void clear() {
// implement clear here
_size = 0;
}
};
And here is the code actually initializes the class object and calls its member functions:
template<class T>
void noisy_push_back(Vector<T>& vector, T item) {
vector.push_back(item);
std::cout << "vector.push_back(" << item << ')' << std::endl;
}
template<class T>
void print_vector(Vector<T>& vector) {
std::cout << "vector =";
for (int i = 0; i < vector.size(); i++) {
std::cout << ' ' << vector[i];
}
}
void test1() {
std::cout << "--- Test 1 output ---\n" << std::endl;
Vector<std::string> vector;
noisy_push_back<std::string>(vector, "wonder");
noisy_push_back<std::string>(vector, "yak");
print_vector(vector);
std::cout << std::endl;
noisy_push_back<std::string>(vector, "bookshelf");
noisy_push_back<std::string>(vector, "euphoria");
print_vector(vector);
}
When I run the program normally, it adds "wonder" and "yak" and then prints the vector just fine. When it tries to push_back("bookshelf") it exits with Process finished with exit code -1073741819 (0xC0000005)
Any ideas?
I tried printing out the vector size right before it exits and it was as expected: size() = 2
Also when I try to run the debugger everything looks normal and the program runs just fine. I am using CLion by the way.
Your compiler should warn you about this; if it does not, turn up your warnings!
You are trying to initialize your
_arraylast, however, since your variables are declared in the order of:Then
_arraywill be initialized first._capacitywill be indeterminate at the time of initialization, thus you have Undefined Behaviour.