class: center middle
Write a function that determines if a path exists between two vertices of a directed graph.
The graph will be represented as an object, each of whose keys represents a vertex of the graph and whose value represents all vertices that can be reached from the aforementioned key.
System Design questions tests the candidate ability to be able to create a system based on a user prompt. A user prompt is either a client telling you what they want or a team making an assumption of what a potential user might want in an idea. What makes this different from an OOP Design question is that this focuses less on the application components themselves and more of the flow of data and how we scale that data based on our understanding of the various trade offs as we modify our system. For the purposes of the REACTO, we will focus mostly on schema design and API design for the main chunk. We can leave a small discussion at the end for scalability but that will be discussed mostly on Friday for our think, pair, share exercise.
User prompt: I want to be able to book movie theater seats online.
You're an industrious programmer that lives off the grid. The local well that you use to fetch water has gone dry, so you've decided to collect rain water to filter; however, your collection device isn't flat.
Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water your collection device is able to trap after raining.