Traveling between country towns, you arrive at a lonely crossroads where some mischief-maker has uprooted the signpost and left it lying by the side of the road.
Without help, how can you choose the right road and continue your journey?
Simply place the sign back in the hole with the correct arrow pointing to the town you've just left. The other arrow(s) will, obviously, now be correctly oriented and you can continue on your leisurely journey, whistling in the dark to keep the bogey man away.