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copied!<pre><code>#include <memory> using namespace std; template<class Real, int Size> class TVector { protected: Real *_values; public: TVector() { // allocate buffer _values = new Real[Size]; } TVector(Real *prValues) { // check first if (prValues == 0) throw std::exception("prValues is null"); // allocate buffer _values = new Real[Size]; // initialize buffer with values for (unsigned int i(0U) ; i < Size ; ++i) _values[i] = prValues[i]; } // Do not forget copy ctor TVector(TVector<Real, Size> const &rTVector) { // allocate buffer _values = new Real[Size]; // initialize with other vector *this = rTVector; } virtual ~TVector() { delete [] _values; } virtual Real &operator[](int iIndex) { // check for requested index if (iIndex < 0 || iIndex >= Size) throw std::exception("requested index is out of bounds"); // index is correct. Return value return *(_values+iIndex); } virtual TVector<Real, Size> &operator=(TVector<Real, Size> const &rTVector) { // just copying values for (unsigned int i(0U) ; i < Size ; ++i) _values[i] = rTVector._values[i]; return *this; } virtual TVector<Real, Size> &operator+=(TVector<Real, Size> const &rTVector) { for (unsigned int i(0U) ; i < Size ; ++i) _values[i] += rTVector._values[i]; return *this; } virtual TVector<Real, Size> operator+(TVector<Real, Size> const &rTVector) { TVector<Real, Size> tempVector(this->_values); tempVector += rTVector; return tempVector; } }; template<class Real> class TVector2: public TVector<Real, 2> { public: TVector2() {}; TVector2(Real *prValues): TVector(prValues) {} TVector2 &operator=(TVector2<Real> const &rTVector) { return static_cast<TVector2 &>(TVector<Real, 2>::operator=(rTVector)); } TVector2 &operator+=(TVector2<Real> const &rTVector) { return static_cast<TVector2 &>(TVector<Real, 2>::operator+=(rTVector)); } TVector2 operator+(TVector2<Real> const &rTVector) { return static_cast<TVector2 &>(TVector<Real, 2>::operator+(rTVector)); } Real &X() { return _values[0]; } Real &Y() { return _values[1]; } }; int main(int argc, char** argv) { TVector2<int> v = TVector2<int>(); v[0]=0; v[1]=1; TVector2<int> v1 = TVector2<int>(); v1.X() = 10; v1.Y() = 15; v = v1; v += v1; v = v + v1; return 0; } </code></pre> <p>Some misc notes:</p> <ol> <li>it's very bad that you use <code>malloc</code> against of <code>new</code>. <code>Real</code> can be POD only to allow <code>vector</code> work well in your case. Use <code>new</code> or provide custom creation policy if you think that <code>malloc</code> provides better performance on PODs. Also do not forget to use <code>delete []</code> instead of <code>free</code> while destroying memory buffer.</li> <li>It's better to perform bounds checking while overloading <code>operator[]</code></li> <li>for better performance use <code>++i</code> instead of postfix form. In former no temporary value is created.</li> </ol>

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