Computer Programming In C.pptx
- 2. COMPUTER
- 3. Architecture of Computer • Input Unit • Central Processing Unit • Output Unit
- 6. Secondary Memory Primary Memory Control Unit (CU) Arithmetic and Logical Unit (ALU) Input unit output unit Memory Data Information Central Processing Unit (CPU)
- 8. Different Units of Memory Data Measurement Size Bit Single Binary Digit (1 or 0) 1 Byte 8 bits (01001011) 1 Kilobyte(KB) 1024 Bytes 1 Megabyte(MB) 1024 Kilobytes 1 Gigabyte(GB) 1024 Megabytes 1 Terabyte(TB) 1024 Gigabytes 1 Peta byte(PB) 1024 Terabytes 1 Exabyte(EX) 1024 Petabytes
- 10. Software Software is a collection of programs and data that tell a computer how to work.
- 11. Computer software can be classified into two types based on its utility 1. Application Software 2. System Software
- 12. Program A computer program is a collection of instructions that can be executed by a computer to perform a specific task. A computer program is usually written by a computer programmer in a programming language. Ex.- C, C++,Python, .net
- 14. Chapter 1 Basics of C
- 15. Contents… • History of C • Features of C • Importance of C • About procedural language • Role of compiler, interpreter • Structure of C program • Algorithm • Flow chart • Debugging of C program
- 18. Features of C 1) Simple C is a simple language in the sense that it provides a structured approach (to break the problem into parts), the rich set of library functions, data types, etc. 2) Machine Independent or Portable Unlike assembly language, c programs can be executed on different machines with some machine specific changes. Therefore, C is a machine independent language. 3) Mid-level programming language Although, C is intended to do low-level programming. It is used to develop system applications such as kernel, driver, etc. It also supports the features of a high-level language. That is why it is known as mid-level language. 4) Structured programming language C is a structured programming language in the sense that we can break the program into parts using functions. So, it is easy to understand and modify. Functions also provide code reusability.
- 19. 5) Rich Library C provides a lot of inbuilt functions that make the development fast. 6) Memory Management It supports the feature of dynamic memory allocation. In C language, we can free the allocated memory at any time by calling the free() function. 7) Speed The compilation and execution time of C language is fast since there are lesser inbuilt functions and hence the lesser overhead. 8) Pointer C provides the feature of pointers. We can directly interact with the memory by using the pointers. We can use pointers for memory, structures, functions, array, etc. 9) Recursion In C, we can call the function within the function. It provides code reusability for every function. Recursion enables us to use the approach of backtracking. 10) Extensible C language is extensible because it can easily adopt new features.
- 20. Importance of C • C is highly portable language i.e. code written in one machine can be moved to other which is very important and powerful feature. • C supports low level features like bit level programming and direct access to memory using pointer which is very useful for managing resource efficiently. • Also used for scripting system applications which form a major part of Windows, UNIX, and Linux operating system. • C programming language is so popular and used so widely because Programmers have opportunities to control how, when, and where to allocate and deallocate memory. Memory is allocated statically, automatically or dynamically. • C is a general-purpose programming language and can efficiently work on enterprise applications, games, graphics, and applications requiring calculations, etc.
- 21. About Procedural Language • A procedural language is a computer programming language that follows, in order, a set of commands. • Examples of computer procedural languages are BASIC, C, FORTRAN, Java, and Pascal. • The focus of procedural programming is to break down a programming task into a collection of variables, data structures, and subroutines, whereas in object- oriented programming it is to break down a programming task into objects that expose behavior (methods) and data (members or attributes) using interfaces.
- 22. Role of Compiler • Compiler, computer software that translates (compiles) source code written in a high-level language (e.g., C) into a set of machine-language instructions that can be understood by a digital computer's CPU. • Compilers are very large programs, with error- checking and other abilities. • Compiler checks source code for syntactical and structural errors and if source code is error free then it generates object code. • The GNU Compiler Collection (GCC) is one such compiler for the C language.
- 23. Role of Interpreter • Computer software that translates source code written in a high-level language into a set of machine-language instructions that can be understood by a digital computer's CPU. • Interpreter is a computer program that directly executes instructions written in a programming or scripting language, without requiring them previously to have been compiled into a machine language program. • Program execution is slow.
- 24. Interpreter • Translates program one statement at a time. • Interpreters usually take less amount of time to analyze the source code. However, the overall execution time is comparatively slower than compilers. • No Object Code is generated, hence are memory efficient. • Programming languages like JavaScript, Python, Ruby use interpreters. Compiler • Scans the entire program and translates it as a whole into machine code. • Compilers usually take a large amount of time to analyze the source code. However, the overall execution time is comparatively faster than interpreters. • Generates Object Code which further requires linking, hence requires more memory. • Programming languages like C, C++, Java use compilers.
- 25. Structure of C program #include<stdio.h> #include<conio.h> void main() { clrscr(); int no1,no2; printf(“Enter nos”); getch(); }
- 26. Preprocessor Directives:- • It is written at the beginning of program. • These lines not end with semicolon. • Only one Preprocessor Directive can appear in one line. • #include <stdio.h> includes the standard input output library functions. The printf() function is defined in stdio.h . • #include <conio.h> includes the console input output library functions. The clrscr() function is defined in conio.h .
- 27. Global Declaration Part • This part of the code is the part where the global variables are declared. • All the global variable used are declared in this part. • The user-defined functions are also declared in this part of the code.
- 28. void main() • The main() function is the entry point of every program in c language. • It is required in all c programs. • Only one main() function in one program. • It begins with the curly brackets and ends with the curly close bracket. • Each main function contains 2 parts- 1. Declaration part It is the part where all the variables are declared. 2. Execution part Each line is statement and terminated by semicolon. E.X.- The printf() function is used to print data on the console. Both the declaration and execution part are inside the curly braces.
- 29. Building Executable version of C program • Create Source Code(.c) • Pre-processing- The preprocessor takes the source code as an input, and it removes all the comments from the source code. • Compilation- The compiler converts this code into assembly code. Assembly- The assembly code is converted into object code by using an assembler. (.obj) • Linking- Linker combine the object code of library files with the object code of our program. The output of the linker is the executable file. (.exe)
- 30. Algorithm • It is logical sequence of steps prepared for solving problem. • It is tool to write job in simple steps in English language. • It is not program. • It guides programmer to prepare the program.
- 31. Efficient Algorithm should have following Characteristics 1. It should be easy and simple in language. 2. It should not repeat task again and again. 3. Every step must be accurate & complete in itself. 4. It can be easily modified if necessary. 5. It should be easily understandable to others & steps should be clear & concise. 6. It should be economical in use of computer time, computer storage and peripherals. 7. It should be correct for clearly defined situations.
- 32. • Algorithm to exchange the value of two variables. Suppose if A and B are two variables. 1) Store the value of A in X. 2) Transfer B value to A. 3) Transfer X to B.
- 33. Flow Chart • After preparing algorithm for given task it can be presented in pictorial form. • The method used to represent algorithm in pictorial form with standard meaningful symbols is known as flow chart.
- 34. Symbols • Rectangular with rounded corners to specify START & STOP known as terminal. It is usually used at start and end of program. • Parallelogram to represent input &output operation. It is also known as input /output symbol. START STOP PRINT INPUT READ
- 35. • Rectangle is used to represent processing or calculating part. • Diamond symbol is used to present decision making step in form of question & logical answer, it is known as “Decision Box.” s=a+b+c is Y=0?
- 36. • Arrows are used to indicate direction of flow of program process. • Small Circle is used to connect incomplete flow chart to its remaining part. It is known as connector. Normally it is used at end of page where flow chart breaks and situations where flow lines cross each other. A A
- 37. Rules to draw Flow Chart 1) The standard symbols should be used. 2) The arrows should be used represent direction of flow. 3) Flow lines should not cross each other. 4) Program flow should be top to bottom.