Declaration of variables in cpp, C/C++ Programming

Assignment Help:

Declaration of Variables:

Variables are declared as follows:

int a;

float b;

 

Assigning value to variables:

int a = 100; Declaring and assigning is called initialization.

float b; Declaring a variable b.

b = 123.456; Assigning value to b.

int a=b=c;

 

Dynamic initialization of variables

int main ( )

{int a = strlen("apple");

cout<<"Total character in the string is"<

return 0;

}

Variables can be declared and initialized at the same time. int main ( )

{int a,b;

cin>>a>>b;

int c=a+b;

cout<<"c is" <

}

In C++  variables  can be declared  anywhere  in  the program  which  will  allow  to do dynamic initialization.  Remember for dynamic initialization the variables must be declared prior to dynamic initialization of new variable.

Reference Variable:

Syntax to define a reference variable is

datatype &reference_variable_name = variable_name;

int y;

int &x = y;

Now the value of x and y will be the same and also if any one of the value is changed the

change will be reflected in the other variable. y =10; Now x is also 10.

x = 20; Now y is also 20.

y = x + 10; Now x and y is 30.

 

Reference through pointer variable:

int x;

int *ptr = &x;

int &y = *ptr;  This is equivalent to int &y=x;

 

In function it is known as call by reference void f_ref(int &x)

{x = x +10;

}

int main ( )

{int m =10; f_ref(m); return 0;

}


Related Discussions:- Declaration of variables in cpp

Define the float data type of c language, Define the Float Data Type of c L...

Define the Float Data Type of c Language? The float is used to define floating point numbers. The Floating point numbers are stored in 32 bits with 6 digits of precision. Eg

Add guts to vs 2008 c++ windows service, Add guts to VS 2008 C++ windows se...

Add guts to VS 2008 C++ windows service Project Description: I have a shell windows32 service written in 2008 VS C++. I want the functionality part started. Need someone too

Car rental payment system, payment system, in c++ only..just use the printf...

payment system, in c++ only..just use the printf or scanf.please

What is your reaction to following line of code? , Q-What is your reaction ...

Q-What is your reaction to following line of code?               delete this; A: This is not a good programming Practice. A good programmer will insist that you must absolute

Read three ints from keyboard and store seperatly , Suppose that three inte...

Suppose that three integer variables intA, intB, and intC have already been defined at the beginning of the main function, write a single C++ statement to read three integers from

AREAUNDERCURVE, Write a program to find the area under the curve y = f(x) b...

Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b. The area under a curve betw

Stuctrue , To store a date use a structure that contains three members date...

To store a date use a structure that contains three members date, month and year. If the dates are equal then display message “Equal” otherwise “Unequal” Program structure: main()

Smuggler, Smugglers are becoming very smart day by day. Now they have devel...

Smugglers are becoming very smart day by day. Now they have developed a new technique of sending their messages from one smuggler to another. In their new technology, they are send

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd