Can i feed my hamster rat and mouse food?

If this was the other way around, I would say it'd be okay for a couple of days. Hamsters have a pretty advanced digestion system and can get bloaty and sick when fed the wrong things. But never fear if you google hamster food you can find some more ''organic?" supplements until you can make it back to your local store. Rats/Mice on the other hand are made to hoard their food. They don't stuff it in their cheeks, although mine likes to sometimes it seems, they like to hide their food. Doing this they burn more energy and need a higher energy/protein diet.

I don't buy rat food, I make my own. I did the same with my hamster too with the store bought mix. Here's a list from my memory you can give hamsters that you may have around the house.

Carrots
Apples
Granola (Good for teeth!)
Cooked red meat (like hamburger meat)
Water Chestnuts
Nuts
Shelled almonds (more fun!)
Bread/Toast (My friend made peanut buttered toast for her hammy)
Fish (fully cooked!)
Eggs (Scrambled/Boiled no fried)
Cheese (in moderation)
Mealworms and crickets (you probably don't have these but for future reference :) )
Dog Biscuits (Try to stay away from some high in protein, and it's good for their teeth!)

Hope that helps!