I think that means that there are events that overlap, and are thus mutually exclusive. If none of the events overlap, then you could just choose all of them.
What I don't get is:
Problem statement: I'm given a set of points, each point being a 3-tuple (x, y, z) where x is the start time of an event, y is the end time of that event and z is the money earned if that event is scheduled/takes place. Now, it is not necessary that all events start or end at a mutually exclusive times. Events may overlap, like A(3, 4, 5) and B(3, 8, 5). Given a set of such events, I've to find a schema such that if the events are scheduled in that order, I'll get the maximum profit.
Why would it matter what order you pick the events? Surely at the end you should just have a set of events which you have chosen and a second set which you have rejected.
