I am using following ways to Allocate & Deallocate memory dynamically
1. Using malloc() and free ()
2. Using calloc() and free()
3 using new and delete operator
4 using stl <vector>

Ok all are different styles. But i looking the better performence.During the use of stl allocation application is very slow. Multiple times calling of new and delete will reduce the application efficiency.

On the shadow of these points how i choose a way which give optimum use of CPU. Which is the best on first 3 ways ?