This chapter describes some problems that involve simulations. In a simulation, a program uses rules to model the behavior of some sort of system. Often, the rules are simplified to make the simulation easier to manage. For example, to simulate the path of an object traveling through a solar system, you might apply forces based on the system's objects individually and at discrete time intervals instead of integrating those forces over time. Similarly, projectile simulations often ignore the effects of wind and air resistance.

Many simulations have a graphical component. Others examine processes that are easier to visualize graphically than by just looking at the data. If you don't have a lot of experience with graphics programming, these problems can give you some useful practice.

Most of the example solutions in this chapter are longer than those described in the previous chapters. Much of that code is relatively straightforward or user interface code, so it isn't presented...