How to charge iphone 4 with no charger?

I lost my charger and the phone is dead

You can't.

Borrow a charger from someone else (any Apple device charger will work, they're all the same) or go buy a new one.

Well you can't of course. You'd have to buy a new charger.

Well you can go to Walgreen's because they have colored chargers for only 8$ or you can borrow a charger.