C how to measure time correctly?

Question

This is the \"algorithm\", but when I want to measure the execution time it gives me zero. Why?

#define ARRAY_SIZE 10000
...

clock_t start, end;

start = cl         


        

Answer 1

This is an unreliable way to actually time number of seconds, since the clock() function is pretty low precision, and your loop isn't doing a lot of work. You can either make your loop do more so that it runs longer, or use a better timing method.

The higher precision methods are platform specific. For Windows, see How to use QueryPerformanceCounter? and for linux see High resolution timer with C++ and Linux?