N meetings in one room

The rule from the Greedy Approach chapters, on your own meetings: sort them by end, then walk them in that order and keep a meeting whenever the last kept one ends before it starts. The meeting that ends first always leaves the most room for the rest.

Each bar is a meeting, numbered by its index; both ends count, so a meeting can't start the minute the last one ends. The dashed lines are the last kept meeting's end and the checked meeting's start. kept lists the meetings held.