//+1 is added for null terminating char //strcpy automatically adds it // refer other all three codes : // case1 , case2 and case3 #include #include using std::cout; using std::endl; using std::exception; using std::out_of_range; class myString { public: myString() : m_iLength(0), m_pBuffer(nullptr) {} myString(const char* p); void append(const char* p, int iPosition); void appendnew(const char* p, int iPosition); ~myString() { delete m_pBuffer; m_pBuffer = nullptr; m_iLength = 0; } void display() { if (m_pBuffer) cout << m_pBuffer << endl; else cout << "Empty string" << endl; } private: int m_iLength; char* m_pBuffer; }; myString::myString(const char* p) { m_iLength = static_cast (strlen(p)); m_pBuffer = new char[m_iLength+1]; strncpy(m_pBuffer, p, m_iLength); //m_pBuffer[m_iLength] = '\0'; } void myString::append(const char* p, int iPosition = 0) { if (iPosition > m_iLength) { throw out_of_range("Cannot append at index more than original string length"); } int inputLen = static_cast (strlen(p)); int newLen = inputLen + m_iLength; char* temp = new char[newLen + 1]; if (iPosition == 0) { strncpy(temp, p, strlen(p)); //temp[inputLen] = '\0'; strncat(temp,m_pBuffer, m_iLength); } //delete original memory delete m_pBuffer; m_pBuffer = nullptr; //copy to current from temp m_pBuffer = new char[newLen + 1]; m_iLength = newLen; strncpy(m_pBuffer, temp, newLen + 1); //delete original delete temp; temp = nullptr; } void myString::appendnew(const char* p, int iPosition = 0) { if (iPosition > m_iLength) { throw out_of_range("Cannot append at index more than original string length"); } int inputLen = static_cast (strlen(p)); int newLen = inputLen + m_iLength; char* temp = new char[newLen + 1]; if (iPosition == 0) { strncpy(temp, p, strlen(p)); //temp[inputLen] = '\0'; strncat(temp,m_pBuffer, m_iLength); } //delete original memory delete m_pBuffer; m_pBuffer = nullptr; //copy to current from temp m_pBuffer = temp; m_iLength = newLen; } int main() { myString obj1; obj1.display(); myString obj2("Ketan"); obj2.display(); try { obj2.appendnew("Lalcheta"); obj2.display(); } catch (const std::exception & ex) { cout << "Issue in append operation : " << ex.what() << endl; } return 0; }

case 4 : mystring