A degree requirement can be represented as a static tree. Each class is represented as a node and directed edges between nodes indicate prerequisite relationships. An edge from node A to node B denotes "class B requires class A as a prerequisite".

Node y-axis location is determined by the course number. (CS 160 is below CS 161. CS 161 is below CS 162, ...). Node x-axis location is physics-based. We should have some basic logic that spaces out nodes for readability.