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 
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