Research on Programming and Debugging Technology of Computer C Language

Transcription

1 Research on Programming and Debugging Technology of Computer C Language Changhua Zhang Hebei Construction Material Vocational and Technical College, Qinhuangdao, China Abstract In the C language programming design process, a small error is likely to affect the entire program running effect, so programmers must ensure the accuracy of programming. In this paper, the author introduced design process of computer C language programming briefly, and analysed the C language programming debugging technology, described two common operating errors, and finally puts forward the debugging method, which is often used in C language programming. Key words: C language, Program design, Debugging technology 1. INTRODUCTION As a senior programming language most widely used in the world at the present stage, the C language has a very strong function of the language, the use of time is very convenient, with strong expression ability and high efficiency. At present, one of the basic computer learning personnel must master is to learn C language applications, many colleges and universities have the C language is a professional basic course of computer related professional to let students understand the basic knowledge of programming. But the concept of C language is relatively complicated, more need to follow the rules in the process of programming, many students will encounter many difficulties in learning, need to take measures to solve this problem. Difficulties in language programming as: 1) The problem is difficult to solve independent compilation errors: At present, most of the C language teaching materials are carried out according to the grammar knowledge sequence, which covers the grammar more content, but learning can be applied to practical problems in personnel content is less. In this case, the students in the process of learning C language is very difficult to fully understand the contents of the C language grammar, and think the grammar of C language knowledge is too complex, resulting in learning effect is not ideal, despite efforts to learn the knowledge of memory, but in the actual process of programming is still there will be a lot of mistakes. Once in the process of programming errors, the student will be very difficult to solve problems in help without the aid of other people, this is because the C language programming error message in English, most students can not understand the narrative content, even if some students can understand English that means, but not their ability to the modified program is correct, or need teachers or other professionals to provide guidance to solve the problem. 2) C language programming is too complex: Generally speaking, most students can compile some relatively simple procedures, but in the face of some of the more complex procedures can easily become unable to start, so that the students when the machine efficiency becomes low, arrangement doesn't always follow the teachers' curriculum, the reason for this is the C language programming method is relatively complicated, students' ability in when the relative lack of analysis program. At the present stage of colleges and universities using C language textbooks are mainly to explain the C language knowledge as the main purpose, when teachers impart knowledge is to cultivate students to master the knowledge of C language as the main purpose, and not to exercise the ability of students to solve problems by their own purpose. In addition, teachers master the knowledge of the C language are mostly derived from the C language teaching materials, this also restricts the student to analyze the question. Therefore, teachers should give students timely guidance to students on the process, when thinking is not clear situation of students in the process of programming, and actively guide students to analyze the programming ideas, improve the students' ability to solve problems independently. 3) C language teaching mode should be improved: At present, most of the teachers still use the traditional teaching model to teach language knowledge C. Generally speaking, teachers will be prepared in advance, when the class will need to explain the knowledge of oral instruction for students, students only need to listen carefully, make notes. However, the C language is a practical subject, students must through the practice operation in order to truly grasp the C language skills, to rely solely on the contents of the textbook memory can not achieve the ideal teaching effect, is not conducive to the students to improve their computer skills. The students in the classroom lectures, thinks they understand all the contents of the teachers, but just started in practice on the stage often feel confused, but also with the help of computer instruction for autonomous learning. Therefore, the traditional C language teaching model is not suitable for the cultivation of computer programming skills of modern students, the relevant departments should be aware of this problem and timely improvement. 346

2 2. RESEARCH STATUS OF C LANGUAGE PROGRAMMING AT HOME AND ABROAD 2.1. Research status of C programming language in China At this stage, China's Internet system has been able to support the C language network course learning, even if not students can also learn online C programming language knowledge. Ding Xingfu is one of the most influential scholars in the field of learning support services in China, and introduced foreign learning support services to the Chinese market earliest. At present, the researchers in educational circles in our country has not formed a unified opinion on learning support service, some scholars believe that the mutual communication and learning support service can effectively realize mutual exchange between teachers and students, all the activities of learning support services should be spread around the students, provide guidance and help for students' learning process by teaching tool. Therefore, learning support services should help students reduce errors in the process of programming and improve students' ability to solve problems independently. Through the continuous improvement of learning support services, not only can we reform the traditional C language teaching activities, but also can update the teaching concept more deeply. Our country has now established its own C language learning system. This software belongs to a C language learning software, the main purpose of research and development is to help students successfully pass the computer grade examination. However, this software is only a teaching aid, and it is not a real learning support system. In recent years, many scholars in our country in the development of electronic performance support system, the specific practice of development projects have emerged, which are of great help to improve the level of education in our country. The C language learning system in China is illustrated in figure 1: Figure 1. C language learning system in China 2.2.Research status of C language programming abroad The research of learning support system in some developed countries is far ahead of our country. The earliest thought is composed of distance education learning support UKOU and distance learning development, this kind of thought in distance education practice process later gradually developed into a relatively mature learning support service thought, and formed a study and practice mode of support service system of higher education is relatively perfect. At this stage, the Open University in Britain is one of the best examples of student support services. Most of the network teaching networks all over the world begins to do research on the learning support service system. The related research of foreign learning support service system provides a very important reference value for the study of learning support service system in china. At present, the research of C language programming learning support system around the world is mainly around the intelligent agent, the purpose of the study is to better apply it to distance teaching. Beginners in the use of learning support system, you can timely understand the changes in their psychological activities, and get learning support system to provide learning guidance and help, and then improve the efficiency of learning C language, better grasp the C language programming rules. Students often learn aimlessly when just beginning to learn C language knowledge, the event will become more complex programming problems at a loss, according to the situation of students, the system will try to understand all kinds of students, to provide students with effective learning, for beginners C language learning in a relatively relaxed environment, so as to the C 3. RESEARCH SIGNIFICANCE OF C LANGUAGE PROGRAMMING DESIGN 3.1.Provide students with the help of C language design 347

3 It is impossible for students to master the relevant concepts and programming rules of C language only when they are listening in class. In the process of computer, students often appear C language programming errors and program programming thinking is not clear and so on, in such circumstances, students will need to get the guidance of the teacher. Many students but teachers need guidance, can not provide help for all students in the machine process, through debugging the C language program design can solve this problem effectively, and help students to improve the efficiency of classroom learning, but also can largely reduce the work pressure of teachers, improve the teaching quality of C in the language classroom. C language in the process as shown in figure 2: Figure 2. C language on the computer 3.2.Exercise students' practical programming ability At this stage, one of the most widely used computer high-level languages in the world is the C language. There are many advantages of C language, including: a variety of services, strong expression ability and wide range of applications. Therefore, C language can be used not only for programming system software, but also for compiling application software. Now, the major colleges and universities in China have C language as a professional basic courses, so that the majority of computer related professional students to learn. According to the modern teaching idea in our country, it is also an important aspect of education to train students' practical ability. But the students appeared a lot of problems in the process of learning C language, these problems restrict the further development of the students, improve the students' ability of computer programming. Through the research of C language programming and debugging technology, it can effectively improve the situation, and cultivate students' practical programming ability. 3.3.Promote the development of computer education C language programming debugging technology is conducive to help students better grasp the relevant knowledge of C language points, and thus effectively improve the efficiency of classroom teaching. At this stage, the important research project in the field of education in China is computer assisted instruction technology. From the point of view of computer aided education, electronic performance support system will become an important part of computer aided instruction in the future. Compared with the traditional mode of computer assisted instruction, electronic performance system can better cultivate students' autonomous learning ability, to meet the various needs of students and social development process, the superiority of it from many aspects of the irreplaceable. At present, the electronic performance system of developed countries in research and development, design and application have been more perfect, but the data on electronic performance system in China the relative shortage of relevant staff need to continue efforts to make up for this shortcoming. 3.4.Innovation of students' learning process At present, countries in the world are committed to the research on the technology of C language program design and debugging, and strive to develop more perfect software to help students better learning C language knowledge. At the present stage of our country has had a computer assisted instruction software for computer grade examination and research and development, but there is no electronic performance system is widely applied to C language teaching assistant. Although many developed countries have successfully set electronic performance system applied to a variety of training courses, but the application scope is very limited, there are still many problems to be solved related personnel. The application of computer assisted instruction software is conducive to innovation in the learning mode of students, let the students out of the traditional teaching mode constraints, exercise their ability to improve computer programming, C language programming ideas, showing a certain degree of professionalism to study and work in the future. 348

4 4. THE JUDGMENT OF C LANGUAGE PROGRAM RUNNING ERROR Generally speaking, the running errors of C language programs can be divided into two kinds: logical errors and programming errors. The logical error refers to the program after the operation end operation results and programmer expected results are not consistent, and the program design error refers to the programming and connection program when no error is found, but in the running after the restart, the output information is chaotic and crash etc.. Typically, running error checking is much harder to compile and link errors. The compiler and linker can check and compile error connection error, although there are some differences between many of the compiler and connection program display error information and the cause of the error and the actual situation, but still has a very high reference value, and basically no runtime error message, run error lookup only to rely on the programmer's work experience, and then obtain the operation error characteristics and approximate location. The programmer looks for a running error scenario, as shown in figure 3: Figure 3. The programmer checks the program This paper describes some common debugging methods for running errors of programs. 4.1.C language algorithm design unscientific C language programming algorithm design is not scientific, is a relatively common logic error, mainly in the absence of a clear definition of the algorithm boundary conditions, such as: please observe the following cycle program: While(count) { Count=count-1; } The purpose of the above statement is to achieve the calculation of the count cycle, but in this cycle, the logic behind the judgment statement of while has always been true, and did not play the purpose of judging the number of cycles, which led to the entire program running into a dead cycle. This error is caused by algorithmic definition errors, and the compiler can not effectively identify the error in the compiler process, so that programmers can find exceptions when they run the program. In addition, known as the three sides of the triangle can use Helen formula to calculate the area of a triangle, but in the calculation we must determine the known composition between the three sides of the triangle exists, programmers often used theorem triangle when using the C programming language, namely the arbitrary triangle on both sides is greater than the third side to judge, once found on both sides and is less than or equal to third, then the three known sides could not make a triangle, there is no need to perform the following procedure. The solution of quadratic equation with one unknown programming as an example to elaborate, the coefficient of programmers use when C programming language mainly by using the quadratic equation with one unknown is solved, but in solving between must be known to determine whether there is a quadratic equation with one unknown solution, the 349

5 quadratic equation with one unknown solution to the situation taking into account the programming process, and thus prevent the program error occurred during operation. To sum up, programmers in the design process must be considered in advance the program in the operation process of the problems that may arise, and before the operation of the program using effective strategies to solve Input errors in programmer programming C language program design input error code is a more common to the logical error when the program is compiled, to avoid this error is the main measure of programmers to improve their rigor, ensure the correctness of each code in the input code. Programmers often appear slack can lead to a series of problems, such as the programmer judgement of "lost" > = "error >", and to judge whether the same code = error is used for transmission of the code assignment "=" etc.. If these errors appear in the C language program design, error messages and errors will occur then the compiler has many kinds of forms, the programmer can hardly be the reason for such mistakes and their code input errors together, leading to greatly increase the programmers in search of wrong operation difficulty. The programmer when the input data are prone to errors, such as: the input character format error will affect the running effect of the entire program, but it is easy to the input of a large amount of data will be the input character format error condition. In order to improve the situation, the programmer can use the file record when manual input a lot of data, and then read and write files in the function of all the program input to the system, by this way can make use of data editor to find the existence of error in input data, but also in the re the calculation or again when input to remind the programmer's attention to this situation, this method has better applicability and scientific computing applications in engineering. Data input program performance programmers tend to use their own programming in the process of developing applications for data processing and transaction management in a relatively complex, the better to replace the often used in C language (scanf) function, this method can be used interactively between input data and user interface, requires the programmer to have good programming skills in C language to complete the work. 5. THE BASIC METHOD OF C LANGUAGE PROGRAMMING AND DEBUGGING TECHNOLOGY 5.1.Standard data check Programmers in the completion of the compiler and the design of the operation environment, you need to run the program and debugging. In general, before running and debugging the C language program, programmers need to test the correctness of the C language program by using a set of standard data that are known to the results. In the process of using the standard data to test the program, the programmer needs to select the standard data according to their own knowledge of the C language and programming experience, as far as possible to choose some relatively simple and representative of the standard data to test, in order to ensure the reliability of the test results, and to help programmers more quickly find the existence of C language problems in the program. Improve the reliability of inspection results. In addition, programmers should also test the adjacency data that affect the C language program, reducing the possibility of running errors in the entire program. 5.2.Multiple tracking test Generally speaking, the procedure is relatively large complex structure is difficult to once through the examination, this program will tend to have some errors, does not exist any possibility of error is very small, so the programmer before the program officially running normally on large programs for multiple tracking test. One of the most commonly used methods for programmers to debug programs is program tracking. Program tracking refers to the programmer to let the program code run sentence by sentence, observe the changes in the results of each sentence code before and after the operation, and record the changes, and carefully analyze the possible problems in the C language program. 5.3.Simplified cycle times The programmer can simplify the program in order to reduce the time needed for debugging, so as to effectively improve the efficiency of the C language program. In the actual simplification process, the programmer can simplify the array module and the number of cycles in the C language program, and save the program language of the unimportant part. However, simplified procedures must follow the principle of moderation, if the simplified procedure is too simple, so it is very difficult to run real effect program performance, such as: in the design of N yuan a equation of the program, simply put the N value is set to 2 is difficult to achieve the purpose of detection. There is no way to guarantee that when N takes a larger value of the program is still valid. 350

6 6. CONCLUSION In a word, C language programming and debugging is a basic course for computer related majors. Because the C language data types and algorithms more, most of the students is difficult to break the inherent mode of thinking just in the learning stage, and will encounter many difficulties in the learning process. In order to better study the course of C language, our educators have conducted in-depth exploration on C language teaching, technology of C language program design, debug analysis, believe that the future of China's C language program design and debugging technology will continue to improve. REFERENCES Wang Yang. Discussion on the application of debugging technology in the teaching of C programming language for non computer majors, education and teaching forum, 2016, (42): Chen Shenglei, Liu Linyuan. The role of debugging technology in the teaching of C programming language, computer knowledge and technology, 2015,11 (24): Huang Minyi. Some discussion on C language programming and debugging technology, science and wealth, 2016, (8): 95-95,96. C.Krstev, and A.Trtovac, (2014). Teaching Multimedia Documents to LIS Students, The Journal of Academic Librarianship, 40 (2), S.Jian-hua, L.hong, (2012). Explore the Effective Use of Multimedia Technology in College Physics Teaching, Energy Procedia, 17, R.A.Sabella, (2010). School counselors perceived importance of counseling technology competencies, Computers in Human Behavior, 26, N.R.Mastroleo, R.Turrisi, (2010). Examination of posttraining supervision of peer counselors in a motivational enhancement intervention to reduce drinking in a sample of heavy-drinking college students, Journal of Substance Abuse Treatment, 39, W.Dai, L.Fan, (2012). Discussion about the Pros and Cons and Recommendations for Multimedia Teaching in Local Vocational Schools,Physics Procedia, 33, R.Khansa, (2015). Teachers Perceptions toward School Counselors in Selected Private Schools in Lebanon,Procedia - Social and Behavioral Sciences, 185,