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C #include statementC Displaying OutputC Reading input from the terminalC Data typesC VariablesC Variable Naming ConventionsC ConstantsC Identifiers & Naming RulesC LiteralsC CommentsC KeywordsC Type QualifiersC TokensC Format SpecifiersC Escape SequencesC preprocessorASCII value in CStatic in CWhat are Compiler ErrorsWhat are Compiler WarningsWhat are Linker ErrorsWhat are Runtime ErrorsWhat are Logical ErrorsCompile time vs RuntimeC program to displays your name  C - Basics Practice Test.1  C - Basics Practice Test.2  C - Basics Practice Test.3  C - Basics Practice Test.4  C - Basics Practice Test.5
C Arithmetic OperatorsC Assignment OperatorsC Relational OperatorsC Logical OperatorsC Increment & Decrement OperatorsC Conditional or Ternary OperatorC Bitwise OperatorsC Type CastingC Sizeof OperatorC Comma OperatorC Operators Precedence and AssociativityC ExpressionsC Evaluation of Expressions  C - Operators Practice Test.1  C - Operators Practice Test.2  C - Operators Practice Test.3
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C ifC if-elseC nested if-elseC if-else-ifC switch-caseC if vs switch-caseC LoopsC while loopC do-while loopC while vs do-whileC for loopC for vs WhileC Nested LoopsC Jump Control structuresC break statementC continue statementC goto statementC continue vs goto statementC return statementC goto vs return statement  C - Control Statements Practice Test.1  C - Control Statements Practice Test.2  C - Control Statements Practice Test.3
C FunctionsC Advantages of Using FunctionsC Function PrototypeC Basic Function DesignsC Programs Using FunctionsC ScopeC Local Variable and Global VariableWhy int main() return 03 Place to declare functionsC RecursionC Base Condition in RecursionC Iteration vs RecursionC Stack Overflow Error in RecursionC Nested functionsC Variable Length Number of ArgumentsC Parameter Passing – Call by value and Call by RefC Passing Strings to FunctionsImplementation of square() functionImplementation of factorial() functionImplementation of pow(x, n) functionImplementation of reverse(int) functionImplementation of countDigits(int) functionImplementation of palindrome(int) functionImplementation of primeNumber(int) function  C - Functions Practice Test.1  C - Functions Practice Test.2
What is Array?One dimensional ArrayAccessing element of 1D arrayReading and displaying elementsPrograms on 1D ArraysTwo Dimensional ArrayAccessing Element of 2D ArrayReading and Displaying ElementsPrograms on 2D ArraysPassing 1D arrays to FunctionsPassing 2D arrays to FunctionsThree Dimensional Array  C - Array Practice Test.1  C - Array Practice Test.2
Strings in CStoring StringsC The String DelimiterC String Literals (String Constants)C Strings vs. CharactersC Declaring and Initialization of StringsC Strings and the Assignment OperatorC String Input Functions / Reading StringsC String Output Functions / Writing StringsC fscanf() and fprintf() FunctionsC Single Character Library FunctionsC String Manipulation Library FunctionsC Programs Using Character ArraysC Array of StringsC Programs Using Array of Strings  C - Strings Practice Test.1  C - Strings Practice Test.2
Pointers in CUnderstanding Memory AddressesDeclare and Initialize Pointer VariablePointer Operators in Csizeof() Operator in CPointer Advantages and DisadvantagesDereferencing/Redirecting Pointer VariablesPointer Declaration versus RedirectionConst Pointer in CVoid Pointer in CNull Pointer in CC Pointer CompatibilityArray of PointersPointer to PointerPointer ArithmeticC Functions Returning PointersC Pointer to FunctionPointers and One-Dimensional ArrayPointers and Two-Dimensional ArrayPointers and StringsDynamic Memory Allocation Functions  C - Pointers Practice Test.1  C - Pointers Practice Test.2  C - Pointers Practice Test.3
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C preprocessor

The C preprocessor is a component of the C compiler that processes source code before actual compilation takes place. Its primary function is to perform text manipulation on the source code based on preprocessor directives and macros. The C preprocessor operates before the actual compilation steps, and its primary job is to prepare the code for the compiler. Here are some key aspects of the C preprocessor:

1. Preprocessor Directives:

Preprocessor directives are special commands that start with a # symbol and are processed by the preprocessor. These directives are not part of the C language but are instructions for the preprocessor. Common preprocessor directives include #include, #define, #ifdef, #ifndef, #endif, and others.

2. Header File Inclusion:

One of the most common uses of the preprocessor is to include header files using #include directives. Header files contain declarations for functions, variables, and other elements that can be used in a C program.
Example: 


    #include <stdio.h>
3. Macro Definitions:

Macros are created using #define directives. They are used to define constants and small code snippets that are replaced by their values or code during preprocessing.
Example: 


    #define PI 3.14159265359
4. Conditional Compilation:

Preprocessor directives like #ifdef, #ifndef, #if, #else, and #endif are used for conditional compilation. These directives allow you to include or exclude parts of the code based on conditions.
Example: 


    #ifdef DEBUG
    printf("Debug mode is enabled.\n");
    #endif
5. File Inclusion and Concatenation:

The #include directive is used to include the contents of other source files into the current source file, allowing you to organize code into separate modules.
The ## operator can be used for token concatenation, which allows you to construct identifiers and symbols dynamically.

6. Stringizing Operator:

The # operator, when used within a macro, converts macro parameters or tokens into string literals.
Example: 


#define STRINGIZE(x) #x
printf("Value: %s\n", STRINGIZE(42));
7. Line Control:

The #line directive allows you to control the line number and file name information that is reported by the compiler. This can be useful for debugging and error messages.

8. Predefined Macros:

The preprocessor provides a set of predefined macros, such as __FILE__, __LINE__, and __DATE__, which can be used to access information about the source code and compilation environment.

The C preprocessor is a powerful tool that allows you to perform text manipulation, create reusable code using macros, and conditionally compile code sections. It plays a crucial role in preparing your source code for compilation by the C compiler.

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