comprog mod 2

• MODULE 2: BRIEF HISTORY OF C++, COMPONENTS
• C++


  One of the world's most popular programming languages, found in operating systems, GUIs, and embedded systems. It is an object-oriented programming language that gives a clear structure to programs and allows code reuse, lowering development costs. C++ is portable and can be used to develop applications that can be adapted to multiple platforms.
• Object-oriented programming


  Gives a clear structure to programs and allows code to be reused, lowering development costs
• History of C++


  1. Bjarne Stroustrup developed C++ at AT&T Bell Labs

  2. C++ was first introduced in 1979 as "C with Classes"

  3. C++ was renamed in 1983

  4. First commercial edition released in 1985

  5. C++ has evolved over the years with new versions released (C++98, C++03, C++11, C++14, C++17)
• C++


  A collection of objects that communicate via invoking each other's methods
• Object


  • Has states and behaviors
• Class


  A template/blueprint that describes the behaviors/states that objects of its type support
• Method


  A behavior, where the logic is written, data is manipulated, and actions are executed
• Instance variable


  Each object has its unique set of instance variables, which create the object's state
• C++ identifier


  A name used to identify a variable, function, class, module, or any other user-defined item. It starts with a letter or underscore and can contain letters, underscores, and digits.
• Whitespace


  Blanks, tabs, newline characters, and comments that separate one part of a statement from another and enable the compiler to identify where one element ends and the next begins
• Enumerated type


  Declares a new type-name along with a sequence of values containing identifiers which have values starting from 0 and incrementing by 1 every time
• What are the modifiers in C++

  • long
  • short
  • signed
  • unsigned
• Variables in C++


  Used to store values that change in the program. Each variable must be given a data type, which determines the memory assigned to the variable.
• Basic types of variables in C++

  • bool
  • char
  • int
  • float
  • double
• int


  Minimum size is short
• Size hierarchy


  • short int
  • int
  • long int
• Size hierarchy for floating point numbers


  • float
  • double
  • long double
• long float is not a legal type and there are no short floating point numbers
• Signed types


  Includes both positive and negative numbers and is the default type
• Unsigned


  Numbers are always without any sign, that is always positive
• Variables in C++


  Used where we need storage for any value, which will change in program
• Variable declaration


  Must be given a datatype, on which the memory assigned to the variable depends
• Basic types of Variables

  • bool
  • char
  • int
  • float
  • double
• Declaration and Initialization


  1. Variable must be declared before they are used

  2. Initialization means assigning value to an already declared variable
• If a variable is declared and not initialized by default it will hold a garbage value
• If a variable is once declared and if try to declare it again, we will get a compile time error
• Variable Scope in C++

  • Local variables (inside a function or block)
  • Formal parameters (in function definition)
  • Global variables (outside all functions)
• Local Variables


  • int a, b, c
  • a = 10
  • b = 20
  • c = a + b
• Global Variables


  • int g
  • g = a + b
• A program can have same name for local and global variables but value of local variable inside a function will take preference
• Types of Operators in C++

  • Arithmetic Operators
  • Relational Operators
  • Logical Operators
  • Bitwise Operators
  • Assignment Operators
  • Misc Operators
• Arithmetic Operators


  • +
  • -
  • *
  • /
  • %
  • ++
  • --
• Relational Operators


  • ==
  • !=
  • 
    
  • >|>=
  • <=
• Logical Operators


  • ||
  • &&
• Bitwise and Bit Shift Operators


  • ~
  • <<
  • >>
  • >>>
  • &
  • ^
  • |
• Assignment Operators


  • +=
  • -=
  • *=
  • /=
  • %=
  • <<=
  • >>=
  • &=