What is the best way to insert range of values into a datastructure

Question

If I have a datastructure which is the fastest way I could insert values into it in a specified range?

For example if I had a method:

myDatastructure var=new myDataStructure();
var.insert(2,1000);

it would mean that I get a most optimised way of getting a datastructure holding values from 2 to 1000 in each of index sequentially.

Answer 1

If you have a C++11 STL, you could use the std::iota() function to insert sequentially increasing values into any container that supports iterators. As for choosing a type of container, C arrays or std:arrays should be the fastest as they require no additional memory allocations while inserting elements.

Answer 2

The fastest way to do this is to not do it. Here's an outline of a class that looks like a read-only array of consecutive integers.

class range {
private:
  int low, high;
public:
  typedef int iterator;
  range(int low, int high) { this.low = low; this.high = high; }
  iterator begin() { return low; }
  iterator end() { return high + 1; }
  int operator[](int index) { return low + index; }
}
...
range r(1, 1000);
for (r::iterator i = r.begin(); i != r.end(); ++i) { ... }

If you need a writable collection, then the answer depends on how you want to modify it after creation.