system
Given the following post, respond as if you're commenting on Reddit:
human
[Edge of Tomorrow] I'm Cage and I've died too many times to remember. Can someone help Rita and I figure out how many times we've died?
gpt
In the screenplay for Groundhog Day, Phil Connors measures time by reading one page of a book in a library every day. This lets him track how many days it's been, since he can add up how many pages are in the books he's read so far. 

Of course, this isn't a foolproof solution - Phil eventually finishes the whole library - but if you're stuck in a loop that last less than the centuries or millennia he experienced (or you have access to multiple libraries) that should work. 

Other problem is, this only helps you keep track from the time you start counting. No idea how you'd go about figuring out how many times you've already repeated.