Chapter 14. Advanced Algorithms
In this chapter we’ll look at two advanced topics: dynamic programming and greedy algorithms. Dynamic programming is a technique that is sometimes considered the opposite of recursion. Where a recursive solution starts at the top and breaks the problem down, solving all small problems until the complete problem is solved, a dynamic programming solution starts at the bottom, solving small problems and combining them to form an overall solution to the big problem. This chapter departs from most of the other chapters in this book in that we don’t really discuss an organizing data structure for working with these algorithms other than the array. Sometimes, a simple data structure is enough to solve a problem if the algorithm you are using is powerful enough.
A greedy algorithm is an algorithm that looks for “good solutions” as it works toward the complete solution. These good solutions, called local optima, will hopefully lead to the correct final solution, called the global optimum. The term “greedy” comes from the fact that these algorithms take whatever solution looks best at the time. Often, greedy algorithms are used when it is almost impossible to find a complete solution, owing to time and/or space considerations, and yet a suboptimal solution is acceptable.
A good source for more information on advanced algorithms and data structures is Introduction to Algorithms (MIT Press).
Recursive solutions to problems are often elegant ...