One important way to work with data is sorting. Its use not only speeds up, but also greatly simplifies the necessary and important process in the field of programming. A narrow sense of this concept among programmers means organizing records in a database.
Sorting methods are relevant to this day, although technological progress has replenished with modern methods of computer technology. Known in his field, the scientist D. Knut claims that almost half of the time in the work on data processing is occupied by their sorting. He points out three reasons that explain this course of things:
- Sorting by choice and other methods is very widespread.
- Its algorithm is often used without much need.
- To solve the tasks, an imperfect model is used.
In order to speed up the data processing, first of all, it is necessary to find a solution to these problems. Programmers are trying to create a structure that itself could use algorithms when needed. If it is created, then work with a large amount of data will significantly accelerate and there will be significant savings in computer resources. But so far this has not happened, and we will consider the current sorting methods.
All of them are divided into internal or external. The essence of the first method is that all records that are sorted are placed in the main memory of the machine. But when this does not happen, external sorting processes are required, and often they are built on the first methods indicated with only minor additions.
Sorting by selection, which will be discussed, refers to the internal. It is on it that we need to dwell in more detail, since such a processing method allows sorting more flexibly and favorably. All its methods are divided into 4 main groups:
- Sort by inserts.
- Counting data processing.
- Exchange process.
- Sort by choice.
It should be noted that clear distinctions between them do not exist, they are closely intertwined and very similar to each other. This determines the presence of a certain connection in their work. The simplest example of working with data processing is counting sorting. It is, as it were, the basis for others, but today it is used extremely rarely. Another method - inserts - is already more important. His idea is that the key under consideration is placed in its proper place. But there are a number of inconveniences and this is negatively reflected in the work on a large number of records. Many highly productive data processing methods are present in exchange sorting. The most popular and most visible in this group is the so-called bubble method. Work in it is based on the following algorithm: a comparison of successive records is performed sequentially and, if the value of the first of them is greater, then they simply swap places. Such a process goes to complete ordering.
And finally, one of the most important, but at the same time simple ways of processing databases is sorting by selection. As already mentioned above, it belongs to the internal group and on its basis several types can be combined. The essence of the method is the choice, and more than once, of one element. Actions are performed in the following order: the smallest element is selected from the list, then it is sent to the output area and its value is replaced with a larger value than all the others. The sequence of operations is repeated until all data in the list is completely selected.
It is clear that for the implementation of the algorithm, the visibility of all elements and, in addition, the area for data output will be required. And here there is the most natural way - sorting is a simple choice, that is, breaking the list into several. With it, you should select the smallest element of the array and exchange it with the first one. Over those elements that remain, such manipulations are again carried out to full compliance.