1 class DoublePointerIter { 2 public: DoublePointerIter(double * start,int len)3 DoublePointerIter(double* start, int len) : start_(start), len_(len) { } begin()4 double* begin() { return start_; } end()5 double* end() { return start_ + len_; } 6 private: 7 double* start_; 8 int len_; 9 }; 10 11