A. Notes
A path between two vertices in a graph is a list of vertices, in which successive vertices are connected by edges in the graph.
The length of a path is the number of edges on the path.
A simple path is a path with no vertex repeated.
A graph is connected if if there is a path from every vertex to every other vertex in the graph.
A graph is traversable if you can draw a path (not simple path) covering all the vertices without retracing any edge. Obviously, a traversable graph is connected.
B. HW
1. In the graph below, how many paths can you find from A to D? Is this graph connected?
How many simple paths from A to F are there? Is this graph traversable?
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2. In the graph below, what is the longest simple path? Is this graph traversable? If you can add an edge, can you make the graph traversable?
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10, no, 5, no
vuwzxy, no, no
10, no, 5, no
v u w z x y, no, no