Join David Gassner for an in-depth discussion in this video A classic CS interview question, part of Code Clinic: C#.
(Intro music) Hello, and welcome to Code Clinic. My name is David Gassner. Code Clinic is a monthly course where a unique problem is introduced to a collection of Lynda.com authors. In response, each author will create a solution using their programming language of choice. You can learn several things from Code Clinic. Different approaches to solving a problem, the pros and cons of different languages, and some tips and tricks to incorporate into your own coding practices.
This month, we're working on a classic computer programming problem called "The Eight Queens." This famous problem is often used during interviews or to demonstrate the utility of a computer language. It requires an understanding of recursion and algorithm design, and can be quite useful as an exercise in learning to program solutions for complex problems. This problem was proposed by Max Bezzel in 1848 and solved by Franz Nauck in 1850.
The problem is simple. Start with a chess board and eight queens. Then, set up the board so that no two queens can attack each other. There's more than one solution. Our challenge is to find them all. We already know there are 92 possible solutions and we already have examples of the solutions in several computer languages. If you've never played chess, you'll need to understand that a queen can attack by moving an unlimited number of spaces in three directions, horizontally, vertically, and diagonally.
This means that no two queens can share a row or a column. Nor can they be located diagonally from each other. In the following movies, I'll show you my solution to the eight queens problem. I'd encourage you to also look at the solutions from other authors in the Lynda.com library. You will be able to compare different author styles and different languages.
David introduces challenges and then provides an overview of his solutions in C#. Challenges include topics such as statistical analysis, searching directories for images, and accessing peripheral devices.
Visit other courses in the series to see how to solve the exact same challenges in languages like C++, Java, PHP, Python, and Ruby.
Skill Level Intermediate
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