Source code online books for professionals by professionals

Partitioning and bin packing. Partitioning involves dividing a set of numbers into two sets with equal sums, while the 
bin packing problem involves packing a set of numbers into a set of “bins” so that the sum in each bin is below a certain 
limit and so that the number of bins is as small as possible. Both problems are NP-hard. (See Chapter 11.)
SAT, Circuit-SAT, k-CNF-SAT. These are all varieties of the satisfaction problem (SAT), which asks you to determine 
whether a given logical (Boolean) formula can ever be true, if you’re allowed to set the variables to whatever truth 
values you want. The circuit-SAT problem simply uses logical circuits rather than formulas, and k-CNF-SAT involves 
formulas in conjunctive normal form, where each clause consists of k literals. The latter can be solved in polynomial 
time for k = 2. The other problems, as well as k-CNF-SAT for k > 2, are NP-complete. (See Chapter 11.)
Searching. This is a very common and extremely important problem. You have a key and want to find an associated 
value. This is, for example, how variables work in dynamic languages such as Python. It’s also how you find almost 
anything on the Internet these days. Two important solutions are hash tables (see Chapter 2) and binary search or 
search trees (see Chapter 6). Given a probability distribution for the objects in the data set, optimal search trees can 
be constructed using dynamic programming (see Chapter 8).