C++ class using

#include <iostream>

using namespace std;

class Bonus
{
private:

    string text;

public:

    void SetValue(string value)
    {
        this->text = value;
    }

    string GetValue()
    {
        return this->text;
    }

    string reverse()
    {
        string reversedText;

        for (int i = text.length() - 1; i >= 0; i--)
        {
            reversedText += text[i];
        }

        text = reversedText;

        reversedText.clear();

        return text;
    }

    void add(char symbol)
    {
        text += symbol;
    }

    void addAt(char symbol, int index)
    {
        string textBeforeTheAddedSymbol;

        int indexesBeforeTheAddedSymbol = text.length() - 1 - index;

        for (size_t i = 0; i < indexesBeforeTheAddedSymbol; i++)
        {
            textBeforeTheAddedSymbol += text[i];
        }

        string textAfterTheAddedSymbol;

        for (size_t i = indexesBeforeTheAddedSymbol; i < text.length(); i++)
        {
            textAfterTheAddedSymbol += text[i];
        }

        text = textBeforeTheAddedSymbol + symbol + textAfterTheAddedSymbol;
    }

    void remove(char symbol)
    {
        for (size_t i = 0; i < text.length() - 1; i++)
        {
            if (text[i] == symbol)
            {
                text[i] = NULL;
            }
        }
    }

    void removeAt(char symbol, int index)
    {
        if (text[index + 1] == symbol)
        {
            text[index + 1] = NULL;
        }
    }

    bool contains(char symbol)
    {
        for (size_t i = 1; i < text.length() - 1; i++)
        {
            if (text[i] == symbol)
            {
                cout << "The word \"" << text << "\" contains the symbol \"" << symbol << "\"." << "\n";
                return true;
            }

            else
            {
                cout << "The word \"" << text << "\" doesn't contain the symbol \"" << symbol << "\"." << "\n";
                return false;
            }
        }
    }

    int containsCount(char symbol)
    {
        int counter = 0;

        for (size_t i = 0; i < text.length() - 1; i++)
        {
            if (text[i] == symbol)
            {
                counter++;
            }
        }

        return counter;
    }
};

int main()
{
    Bonus text;

    string textToEnter;

    cout << "Enter a text: ";
    cin >> textToEnter;

    text.SetValue(textToEnter);

    cout << "\n";

    char symbolToAdd;

    cout << "Symbol to be added: ";
    cin >> symbolToAdd;

    text.add(symbolToAdd);

    cout << "\n";

    cout << "The word now looks like this: " << text.GetValue() << "\n";

    cout << "\n";

    cout << "Symbol to be added at index." << "\n";

    char symbolToAddAtIndex;

    cout << "Symbol: ";
    cin >> symbolToAddAtIndex;

    int indexToAdd;

    cout << "Index: ";
    cin >> indexToAdd;

    text.addAt(symbolToAddAtIndex, indexToAdd);

    cout << "\n";

    cout << "The word now looks like this: " << text.GetValue() << "\n";

    cout << "\n";

    char symbolToRemove;

    cout << "Symbol to be removed: ";
    cin >> symbolToRemove;

    text.remove(symbolToRemove);

    cout << "\n";

    cout << "The word now looks like this: " << text.GetValue() << "\n";

    cout << "\n";

    cout << "Symbol to be removed at index." << "\n";

    char symbolToRemoveAtIndex;

    cout << "Symbol: ";
    cin >> symbolToRemoveAtIndex;

    int indexToRemove;

    cout << "Index: ";
    cin >> indexToRemove;

    text.removeAt(symbolToRemoveAtIndex, indexToRemove);

    cout << "\n";

    cout << "The word now looks like this: " << text.GetValue() << "\n";

    cout << "\n";

    char symbolContains;

    cout << "Wanted symbol to be contained: ";
    cin >> symbolContains;

    cout << "\n";

    text.contains(symbolContains);

    cout << "\n";

    string timePeriod;

    text.containsCount(symbolContains) == 1 ? timePeriod = "time" : timePeriod = "times";

    cout << "The symbol \"" << symbolContains << "\" can be seen " << text.containsCount(symbolContains) << " " << timePeriod << " in the word \"" << text.GetValue() << "\"." << "\n" << "\n";

    cout << "When it's reversed, it looks like this: " << text.reverse() << "\n";

    return 0;
}