Simples, time for HAROLD'S UNIVERSITY PLAN! Okay buy like a box of cereal, which should last a weekish and they cost like a pound so you've got 99 pounds left. I don't know to be honest, buy excessive amounts of bread and a toaster to carry around with you for lunches? Oh, don't forget the spreads, my dude! And for your dinners, well you can figure that out, be diverse you know don't follow a plan completely. Good luck ,do not perish by rationing too much my dude.