I heard that if I want to dispose unlimited number of memory cells I use the operator new. For example : I want to have a table[x] and x is unknown then I wanna reserve some place (because I don't know x will be 10 or 4503 or 15). I do it with the operator new, *index and alternatively with delete (if I want to delete *index).
I understand it.
But in my book is :
index = new double "
So : if I know that table has got 15 elements why I use the operator new?
Maybe there is more than one application of new?