Welcome to the inaugural Public Transport Schedule Interpretation Fun Challenge (PTSIFC), in which I invite you to pit your wits against the vagaries of riding public transport in an unknown land.

The task is simple, and I will not subject you to the horrors of finding out which bus you have to take and where the bus stop is. No, for now, you merely have to devise an algorithm to determine how long you will have to wait until your bus or tram arrives. At your disposal is a schedule (example here) and your own wristwatch.

Solution under the fold.