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

Explain object conversions, Object Conversions Just like initialization...

Object Conversions Just like initialization, conversions are also done automatically when an object of a derived class is assigned to an object of the base class. Though, the c

Explain floating literal, Floating  literal They can be written in comm...

Floating  literal They can be written in common decimal as well as scientific notation (floating point representation). By default it is of type double. F, L is applied only to

Write a program to find the area under the curve y =, Write a program to fi...

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.   #include float start_poin

C program for function of merge , C Program for FUNCTION OF MERGE #inc...

C Program for FUNCTION OF MERGE #include conio.h> #include stdio.h> char cot(char a[],char b[]); void main() {           char a[50],b[50];           clrscr()

Memory management by c program, Memory management by c program: Write ...

Memory management by c program: Write a program to memory management in c program unsigned max( unsigned, unsigned );   int BaseMemBlocks::allocBlock( size_t sz )

Stack and queues, Using Figure 10.2 as a model, illustrate the result of ea...

Using Figure 10.2 as a model, illustrate the result of each operation in the sequence ENQUEUE.Q; 4/, ENQUEUE.Q; 1/, ENQUEUE.Q; 3/, DEQUEUE.Q/, ENQUEUE.Q; 8/, and DEQUEUE.Q/ on an i

Static optimality theorem, Question 1 Describe the following with respect ...

Question 1 Describe the following with respect to pointers in C language- Pointers and Arrays Usage of Pointers in functions Write programs in C to demonstrate the

Area under Curve, #queWrite a program to find the area under the curve y = ...

#queWrite 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 between two points c

How can one encourage his (older) compiler , Q: How can one encourage his (...

Q: How can one encourage his (older) compiler to check new to see automatically if it returns NULL?       A: His compiler eventually will. If he contain an old compiler wh

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