quote:Original post by jollyjeffers
Kippesoep - I''ve seen some stuff on those vectors things before (STL right?), but does that slow things down at all?
a.) No.
b.) Do you think using new and delete would be any faster, either for you (in terms of typing out the extra statements while preserving your data) or for your code (execution time)?
Using resize isn''t particularly efficient anyways. What you should do is call reserve when you first construct your vector (a design flaw, but that''s another discussion) to limit unecessary resizing early on, then simply use push_back and/or push_front to add additional elements as needed. The vector will take care of resizing itself, and in a more efficient way (when it reaches capacity, it roughly doubles its size so it doesn''t have to resize so frequently).
Finally, if the time taken to resize the vector is a major bottleneck in your algorithm, you don''t want a vector; you want a constant insertion time structure like a list or unsorted associative array. vector''s attraction is the same as that of arrays - constant time random access.
Redimensioning arrays. I know (using pointers) that to create an array I can do:
int *pArray = new int[10000]
However, once I''ve created this array, how could I add new elements and/or delete elements (the latter isn''t so important).
I''ve been using VB for so long now, that I''m used to using (in VB!)
Dim Array() as long
redim Array(10000) as long
redim preserve Array(10001) as long ''add another element
I don''t believe the same is not possible in C++ 
but bjarne Stroustrup''s book doesn''t seem to mention how to do it (or if it does, I missed it!).
Any quick hints/suggestions?
many thanks in advance,
Jack;
