#include <iostream>


using namespace std;

class Vector {

public:

    Vector() : size(0), capacity(4), arr (new int[4]) {}

    Vector(const int vector_capacity) : size(0), capacity(vector_capacity), arr(new int[vector_capacity])  {}

    void Push_back(const int value) {
        if (size == capacity) {
            int* temp = new int[capacity * 2];
            for (int i = 0; i < size; i++) {
                temp[i] = arr[i];
            }
            delete[] arr;
            arr = temp;
            capacity *= 2;
        }
        arr[size] = value;
        size++;
        total_number_elements++;
    }

    void Pop_back() {
        if (size > 0) {
            arr[size - 1] = 0;
            size--;
            total_number_elements--;
        }
    }

    int Size() {
        return size;
    }


    int Capacity() {
        return capacity;
    }

    void Insert(const int index, const int value) {
        if (index < 0 || index >= size) {
            cout << "Invalid index" << endl;
            return;
        }
        if (size == capacity) {
            int* temp = new int[capacity * 2];
            for (int i = 0; i < size; i++) {
                temp[i] = arr[i];
            }
            delete[] arr;
            arr = temp;
            capacity *= 2;
        }
        for (int i = size; i > index; i--) {
            arr[i] = arr[i - 1];
        }
        arr[index] = value;
        size++;
        total_number_elements++;
    }

    void Erase(const int index) {
        if (index < 0 || index >= size) {
            cout << "Invalid index" << endl;
            return;
        }
        for (int i = index; i < size - 1; i++) {
            arr[i] = arr[i + 1];
        }
        arr[size - 1] = 0;
        size--;
        total_number_elements--;
    }

    int GetValue(const int index) {
        if (index < 0 || index >= size) {
            cout << "Invalid index" << endl;
            abort;
        }
        return arr[index];
    }

    void SetValue(const int index, const int value) {
        if (index < 0 || index >= size) {
            cout << "Invalid index" << endl;
            return;
        }
        arr[index] = value;
    }

    ~Vector() {
        delete[] arr;
    }

private:
    int size;
    int capacity;
    int* arr;
};

int Vector::total_number_elements = 0;

int main() {

    Vector my_vector;

    my_vector.Push_back(10);

    cout << "Size: " << my_vector.Size() << " Capacity: " << my_vector.Capacity() << endl;

    my_vector.Erase(0);

    cout << "Size: " << my_vector.Size() << " Capacity: " << my_vector.Capacity() << endl;

    for (int i = 0; i < 10; i++) {
        my_vector.Push_back(i + 1);
    }

    for (int i = 0; i < my_vector.Size(); i++) {
        cout << my_vector.GetValue(i) << " ";
    }
    cout << endl;

    cout << "Size: " << my_vector.Size() << " Capacity: " << my_vector.Capacity() << endl;

    my_vector.SetValue(2, 13);

    my_vector.Insert(4, 12);

    for (int i = 0; i < my_vector.Size(); i++) {
        cout << my_vector.GetValue(i) << " ";
    }
    cout << endl;

    cout << "Size: " << my_vector.Size() << " Capacity: " << my_vector.Capacity() << endl;

}