Seemingly Easy MQL4 Question

Hello Programmers!

I need a little help with a simple piece of code that I cannot for the life of me find documentation to reference.

I need to compare the current tick with the previous tick.

ie.
int i = current tick - previous tick


Is this possible in with Metatrader?
(I would think so...)

Thanks!

Make these variables global

double CurrentTick;
double PreviousTick;

start()

PreviousTick = CurrentTick;
CurrentTick = Ask;

Thanks Ronald

I figured it was something simple, I just don't know all the syntax for this language.

Happy Trading!