Entering size of an array

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Originally Posted by ~Kyo~

It is standard to put any calls to new in a try block in case it does throw an exception.

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It is standard to use RAII. Having an exception be thrown in the face of a single call to new in such a case is safe: the exception will just be propagated. You need the try block because you need to delete if an exception is thrown later on, but with RAII that worry is eliminated.

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Originally Posted by ~Kyo~

All I did was choose a name for an example. To my knowledge you could change that to anything and have the code still work.

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Sure, but for all your talk about avoiding overhead, you described a solution that has a great deal more overhead than what I proposed in terms of the invocations of new[] in the loop, compared to say, two invocations of new[].

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Originally Posted by ~Kyo~

Also to my knowledge vector is fine unless you expand alot on it in which case it does end up calling new and copying itself.

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That may well be fine. The complexity of push_back is amortized O(1) because of how the vector's capacity grows (i.e., by a factor, not a constant).

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Originally Posted by ~Kyo~

In theory you COULD define larger bounds on a <datatype here> ** and have the same flexibility.

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You could define a larger bounds on a vector<datatype here> and have the same flexibility, as well as the same possible space wastage.

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Originally Posted by ~Kyo~

Vector uses new I am very much sure of that being dynamic and all. Just because you don't see the code when you implement it does not mean it is never called.

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The vector uses the provided allocator, which may or may not use the new[] that you have in mind.

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Originally Posted by ~Kyo~

Your still saving overhead if you are not resizing that is my point

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If saving the space that would have been used to store the capacity really was your point, then it is a non-issue: you could use the up and coming std::unique_ptr with a custom deleter, or implement your own non-expandable vector class template (extremely easy since it is err... not expandable).