(Mechanics) Run or walk in the rain

Question:

Should you run or walk when you have to cross the street in the

rain without an umbrella? Running means spending less time in the rain, but, on the other hand, since you are running into some rain, you might end up wetter than if you had walked. Try to do a rough calculation, taking your body as a rectangular object. Using such a model, can you tell if your answer (whether to run or walk) depends on whether the rain is falling vertically or at a slant?