Читать книгу Algorithms For Dummies - John Paul Mueller, John Mueller Paul, Luca Massaron - Страница 36

The brute-force solution, described in the previous section, has a serious drawback. It looks at the entire problem at one time. It’s sort of like going into a library and hunting book by book through the shelves without ever considering any method of making your search simpler. The divide-and-conquer approach to book searches is different. In this case, you begin by dividing the library into children’s and adults’ sections. After that, you divide the adults’ section into categories. Finally, you search just the part of the category that contains the book of interest. This is the purpose of classification systems such as the Dewey Decimal System (see https://mcpl.info/childrens/how-use-dewey-decimal-system). The point is that divide and conquer simplifies the problem.

The divide part of divide and conquer is an essential way to understand a problem better as well. Trying to understand the layout of an entire library could prove difficult. However, knowing that the book you want to find on comparative psychology appears as part of Class 100 in Division 150 of Section 156 makes your job easier. You can understand this smaller problem because you know that every Section 156 book will contain something about the topic you want to know about. Algorithms work the same way. By making the problem simpler, you can create a set of simpler steps to finding a problem solution, which reduces the time to find the solution, reduces the number of resources used, and improves your chances of finding precisely the solution you need.