1) Introduction to C language (C self-study) and self-testing

1) Introduction to C language (C self-study) and self-testing
C Language History

The first advanced language in the world is "ALFOL", and the predecessor of C is ALGOL. In 1970, Ken Thompson of Bell Laboratory further simplified BCPL (Basic composite programming language) and highlighted the hardware processing capability, the first letter "B" of "BCPL" is used as the name of the new language. At the same time, the UNIX operating system is compiled in Language B. In 1972, brown W Kanhan and Dennis M LiQi of Bell's laboratory improved and expanded language B, and on the basis of retaining the powerful hardware processing capabilities of Language B, the data type is expanded, the versatility is restored, and the second "BCPL" letter C is used as the name of the new language. Since then, the two have collaborated to rewrite the UNIX operating system. C language along with UNIX systems has become a very popular advanced computer language. In order to break away from the UNIX System and become a general computer language that can run on any computer, two people wrote a book "C programming language" in 1977.

Main features of c language:

1) it is closer to hardware than other advanced languages, easier to describe algorithms than low-level languages, and easier to compile, read, troubleshoot, and modify programs. It can be said that there are both advanced and low-level languages.

2) data types and operators are rich, making program design and algorithm description easier and more convenient.

3) The syntax structure is simple and the number of statements is small, which is easy to learn.

4) It is a structured programming language that provides complete program control statements (select statements and loop statements) and is suitable for structured programming methods.

5) It is a modular programming language and is suitable for the development and debugging of large-scale software.

6) it provides a large number of library functions for calling and simplifies program design.