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Language: C++
Expertise: Intermediate

Feb 15, 2005

In most situations, it doesn't make much sense to create vectors of pointers to the short datatype. Compare these two code samples:

vector<short*> myvector; //bad code.
short * pS = new short;
*pS = 2;
myvector.push_back(ps);

//***********************************

vector<short> myvector; // good code
myvector.push_back(2);

//***********************************

You'll note that each element in vector<short> takes two bytes, whereas each element for vector<short*> takes four bytes (for the pointer on an Intel 32-bit machine) and two additional bytes on the heap (for the new short). So a short* takes a total of six bytes!

These unneccessary calls to new and delete leads to heap fragmentation and performance bottlenecks—and they can be avoided easily by using vector<short>.

vector<short> is much cleaner with lesser space requirements.