programming-for-dummies

376
Understanding Graphs
457 miles
504 miles
406 miles
387 miles
509 miles
Figure 5-1:
Modeling
a map of
different
cities.
153 miles
287 miles
325 miles
You could model this problem as a two-dimensional array like this:
Los San Las San Salt Lake
Angeles Diego Vegas Francisco City
Los Angeles 0 153 287 387 X
San Diego 153 0 325 509 X
Las Vegas 287 325 0 504 406
San Francisco 387 X 504 0 457
Salt Lake City X X 406 457 0
Although this two-dimensional array accurately models the map of different
city distances, it’s not easy to understand what this data represents. A better
data structure would be a graph.
Understanding Graphs
A graph is typically created by using a linked list that can point to multiple
nodes. As a result, a graph doesn’t follow a linear structure but a more haphazard
appearance, which makes it perfect for modeling non-linear data,
such as the map of different cities and distances, as shown in Figure 5-2.