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course content

Course Content

C Basics

1. Introduction

Structure of the C-ProgramEssentials of C ProgramHow to Run the Program?

2. Data

DataVariablesPrintfIntroduction to ArraysTwo Dimensional ArraysChar and StringSizeofPrintf PracticeSizeof Practice

3. Operators

Assignment, Comparison, Not Equal ToSum, Difference, Increment, DecrementMultiplication, Division and ModuloComparison OperatorsComparison Operators PracticeLogical OperatorsLogical Operators Practice

4. Control Statements

If-else Operatorif-else Operator PracticeTernary OperatorSwitch, BreakWhile, Do-WhileFor, ContinueFor Loop Practice

5. Functions

Structure of the FunctionDeclaration, Type and ReturnArgumentsPassing ArgumentsHeader, Prototypes Void, Recursion

6. Pointers

Pointers are around UsReferences and DereferencesPointersMalloc and FreeFunctions, Arrays and Two PointersVoid

C Basics

References and DereferencesReferences and Dereferences

Pointers are built around two operators:

  • The address-of operator &.
  • The dereference operator *.

Address-of Operator

The address-of operator, represented by &, allows us to directly interact with our computer's RAM. Using & lets you obtain the actual memory address of an object.

c

Main.c

Note

%p is the format specifier used for addresses (pointer).

Addresses are typically expressed in hexadecimal notation.

Think of the & operator as identifying your home's address using your name.

Dereference Operator

Conversely, the * operator gives you the resident's name when given their address. So, how can we employ this operator if we're not directly dealing with addresses? If you have an expression like &x, which returns the address of the x variable, applying the * operator to it (*&x) gives you the value of the variable stored at that address.

Note

Essentially, *&x is the same as x.

c

Main.c

Note

Don't mix up the dereference operator (*x) with the multiplication operator (x*y).

Task

  • Create an integer array of 5 elements and populate it.
  • Retrieve the address of the third element.
  • Increment the address of the third element (i.e., address + 1).
  • Attempt to dereference the address obtained in the previous step.

Everything was clear?

Section 6. Chapter 2
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course content

Course Content

C Basics

1. Introduction

Structure of the C-ProgramEssentials of C ProgramHow to Run the Program?

2. Data

DataVariablesPrintfIntroduction to ArraysTwo Dimensional ArraysChar and StringSizeofPrintf PracticeSizeof Practice

3. Operators

Assignment, Comparison, Not Equal ToSum, Difference, Increment, DecrementMultiplication, Division and ModuloComparison OperatorsComparison Operators PracticeLogical OperatorsLogical Operators Practice

4. Control Statements

If-else Operatorif-else Operator PracticeTernary OperatorSwitch, BreakWhile, Do-WhileFor, ContinueFor Loop Practice

5. Functions

Structure of the FunctionDeclaration, Type and ReturnArgumentsPassing ArgumentsHeader, Prototypes Void, Recursion

6. Pointers

Pointers are around UsReferences and DereferencesPointersMalloc and FreeFunctions, Arrays and Two PointersVoid

C Basics

References and DereferencesReferences and Dereferences

Pointers are built around two operators:

  • The address-of operator &.
  • The dereference operator *.

Address-of Operator

The address-of operator, represented by &, allows us to directly interact with our computer's RAM. Using & lets you obtain the actual memory address of an object.

c

Main.c

Note

%p is the format specifier used for addresses (pointer).

Addresses are typically expressed in hexadecimal notation.

Think of the & operator as identifying your home's address using your name.

Dereference Operator

Conversely, the * operator gives you the resident's name when given their address. So, how can we employ this operator if we're not directly dealing with addresses? If you have an expression like &x, which returns the address of the x variable, applying the * operator to it (*&x) gives you the value of the variable stored at that address.

Note

Essentially, *&x is the same as x.

c

Main.c

Note

Don't mix up the dereference operator (*x) with the multiplication operator (x*y).

Task

  • Create an integer array of 5 elements and populate it.
  • Retrieve the address of the third element.
  • Increment the address of the third element (i.e., address + 1).
  • Attempt to dereference the address obtained in the previous step.

Everything was clear?

Section 6. Chapter 2
toggle bottom row
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