Labolatory work 3(1)

#include <iostream>
#include <cstring>


using namespace std;

class Line {
    char *line;
    int length = 0;

    void checkIndex(int index) {
        if (index < 0 || index > length - 1) {
            throw "Incorrect index: your index: " + to_string(index) + ", line length: " + to_string(length - 1);
        }
    }

public:


    Line() {
        string defaultLineText = "Hello, world!";
        this->line = new char[defaultLineText.length() + 1];

        length = (int) defaultLineText.length() + 1;
        strcpy(this->line, defaultLineText.c_str());
        cout << "constructor L";
    }

    explicit Line(const string &line) { //avoids implicit calls to constructor
        this->line = new char[line.length() + 1];

        length = (int) line.length() + 1;
        strcpy(this->line, line.c_str());
        cout << "constructor L";
    }

    explicit Line(const Line &userLine) { // copy constructor
        length = userLine.length;
        delete[]line;
        line = new char[length];
        for (int i = 0; i < length; i++) {
            line[i] = userLine.line[i];
        }
        //userLine->line = line;
        cout << "constructor L";
    }

    ~Line() {
        delete[] line;
        cout << "destructor L" << endl;
    }

    void printArr(char *arr, int arrLength) {
        for (int i = 0; i < arrLength; i++) {
            cout << arr[i];
        }
        cout << endl;
    }

    void clear() {
        length = 1;
        char *newLine = new char[1];
        newLine[0] = '\0';
        delete[]line;
        line = newLine;
    };

    void deleteSymbolFromTheEnd() {
        deleteSymbolByIndex(length - 2);
    }

    void deleteFromTheBeginning() {
        deleteSymbolByIndex(0);
    }

    void deleteSymbolByIndex(int index) {
        checkIndex(index);
        char *newLine = new char[length - 1];
        for (int i = 0; i < index; i++) {
            newLine[i] = line[i];
        }
        for (int i = index + 1; i < length; i++) {
            newLine[i - 1] = line[i];
        }
        length--;

        delete[]line;
        line = newLine;
    }

    void insertTextFromIndex(int index, const string &userLine) {
        checkIndex(index);
        char *newLine = new char[length + userLine.length()];

        for (int i = 0; i < index; i++) {
            newLine[i] = line[i];
        }

        for (int i = 0; i < userLine.length(); i++) {
            newLine[i + index] = userLine[i];
        }

        for (int i = index; i < length; i++) {
            newLine[i + userLine.length()] = line[i];
        }

        delete[] line;
        line = newLine;
        length += userLine.length();
    }

    void print() {
        printArr(line, length);
    }

    string getLine() {
        return line;
    }

    int getSize() {
        return length;
    }

    Line operator=(Line &other) {
        char *newLine = new char[other.getLine().size() + 1];
        string str = other.getLine();
        std::copy(str.begin(), str.end(), newLine);
        newLine[other.getLine().size()] = '\0';
        line = newLine;
        newLine = nullptr;
        length = (int) (other.getLine().size()) + 1;
        delete[] newLine;
    }

};

class Text {
    Line *text;
    int length;

    int numberOfSentences = 0;

public:
    Text(Line *line) {
        text = line;
        length = line->getSize();
        numberOfSentences++;
        cout << "constructor T";
    }

    ~Text() {
        delete text;
        cout << "destructor T";
        //text->~Line();
    }

    void add(Line *line) {
        text->insertTextFromIndex(length - 1, " " + line->getLine());
        length += line->getSize();
        numberOfSentences++;
    }

    void print() {
        text->print();
    }

    int getLength() {
        return length;
    }

    string getText() {
        return text->getLine();
    }

    int getNumberOfSentence() {
        return numberOfSentences;
    }

    Text operator=(Text otherText) {
        text = new Line(otherText.getText());
        length = otherText.getLength();
        numberOfSentences = otherText.getNumberOfSentence();
    }

    Text operator+(Text &otherText) {
        int otherTextLength = otherText.getLength();
        text->insertTextFromIndex(length - 1, otherText.getText());
        length += otherText.getLength();
        //cout << "other length: " + to_string(otherText.getLength()) + "  " + to_string(length);
    }

};

int main() {
    try {
    Line converter("Hello, dudes!");
    converter.print();
    converter.insertTextFromIndex(1, "[new_word]");
    converter.print();
    converter.deleteSymbolByIndex(5);
    converter.print();
    converter.deleteFromTheBeginning();
    converter.print();
    converter.deleteSymbolFromTheEnd();
    converter.print();

    Line newLine("new_line");
    converter = newLine;
    converter.print();

    Text text(&converter);
    text.print();
    cout << " error " << endl;
    Line *anotherLine = new Line("RANDOM_WORD");
    text.add(anotherLine);
    text.print();
    text = text + text;
    Text newText(new Line("virus_WORD_virus"));
    text = newText;
    text.print();

    } catch (const char *return_exception) {
        cout << return_exception;
    }

}