How many keywords in c plus plus and what are they?

Answer 1

The const keyword is the antonym of variable. While a variable is a volatile identifier and can change its value at any time, a constant identifier is non-volatile and must be assigned a value at the point of instantiation. Whenever you declare a constant you are allowing the compiler to assure you that the value will never change, whether purposely or by programming error. By allowing the compiler to assure constance, you do not need to manually check if the value has been altered. As with many other things in C++, the more responsibility you hand to the compiler, the more robust your programs will be.

Answer 2

Theres a few... Some of them are:

int

char

double

float

long

short

unsigned

signed

bool

for

do

while

if

else

return

using

namespace

typedef

template

typename

and

break

case

switch

class

const

default

enum

false

true

or

private

public

sizeof

This is not all C++ keywords!

Answer 3

A keyword in any computer language is a reserved word. What this means is that you cannot declare a user-defined name using a keyword -- they are exclusive to the language itself. In C++, all keywords and user-defined names are case-sensitive, so while you cannot declare the name 'virtual' because it is a keyword, you can declare the names such as 'Virtual', 'VIRTUAL', ViRtUaL, and so on. However, to avoid any chance of confusion, it's best to avoid using names that resemble keywords.

Keywords in C++ include all names with a double underscore or that lead with an underscore followed by an uppercase letter, as well as all of the following major keywords:

• alignas (since C++11)
• alignof (since C++11)
• and
• and_eq
• asm
• auto
• bitand
• bitor
• bool
• break
• case
• catch
• char
• char16_t (since C++11)
• char32_t (since C++11)
• class
• compl
• const
• constexpr (since C++11)
• const_cast
• continue
• decltype (since C++11)
• default
• delete
• do
• double
• dynamic_cast
• else
• enum
• explicit
• export
• extern
• false
• final (since C++11)
• float
• for
• friend
• goto
• if
• inline
• int
• long
• mutable
• namespace
• new
• noexcept (since C++11)
• not
• not_eq
• nullptr (since C++11)
• operator
• or
• or_eq
• override (since C++11)
• private
• protected
• public
• register
• reinterpret_cast
• return
• short
• signed
• sizeof
• static
• static_assert (since C++11)
• static_cast
• struct
• switch
• template
• this
• thread_local (since C++11)
• throw
• true
• try
• typedef
• typeid
• typename
• union
• unsigned
• using
• virtual
• void
• volatile
• wchar_t
• while
• xor
• xor_eq

Answer 4

It has various meanings depending on the context.

A virtual method in a base class implies the method may be overridden by a derived class, in which case calling that method on the base class calls the method in the most-derived class that implements that method. This is achieved via the virtual table (v-table), so there is no need to determine the actual type of the derived class at runtime.

A pure-virtual method in a base class implies the class is abstract and must be derived from, and that a derivative must implement the method (or it becomes abstract itself). You cannot instantiate abstract classes. They are intended purely to provide a common interface to their derivatives.

A virtual base class is a class that is common to two or more derived classes that may be combined in a multiple-inheritance class. If the derived classes declare the base class virtual, the derived classes will share the same instance of the base class, and the multiple-inheritance class will inherit just one instance of the base class from those derived classes. If the derived classes do not declare the base class virtual, the derived classes have separate instances of the base class, which inevitably leads to an ambiguity in the multiple-inheritance class.

Answer 5

Keywords are words that are reserved by C++ and cannot be used as variable names, function names or user-defined data types. Keywords convey special meaning when used in code. The following are examples of reserved keywords:

int

void

friend

class

struct

if

else

while

do

If you want to know all the keywords in C++, see related links, below.

Answer 6

It is hard to say exactly because some vendors of C++ compilers introduce more keywords. At least 74 keywords are available as a minimum number.

Answer 7

To overload an operator. ie to write operator functions