How to find out which nested for loop is better?

Question

Somebody asked me a question: Which one is the fastest among the below two scenario:

Case 1: assume int count = 0;

for (int i = 0; i < 10; i++)
{
           


        

Answer 1

Actually, it is in general not a good idea to try to optimize yourself for such details, because mostly the compiler is much better at it (as long as the algorithm is not changed).

The number of loops is equal.

It might be that the second is a bit faster, because the initialization of the second loop only happens 5 times instead of 10, but I doubt that would really gain some noticable change.

The best way is to use a profiler or even better: analyze the generated assembly code.