Explain call by reference, C/C++ Programming

Assignment Help:

Call by Reference

Passing variables(parameters) to a function in C can be done in two ways - pass by value, also called as call by value and pass by address or also known as call by address. C++ though , gives one more way to call a function - call by reference. In call by value , a copy of the actual contents of the variables is passed to the function. In this case, alters made to the formal variable , as they are called, are not reflected back in the calling function. Passing an address permits changes to be made directly to the memory, which are occupied by the actual variable.

Though, a call by address requires the formal variable to be considered as pointer and therefore the indirection operator has to be used with them. A reference on the other hand, is another name, for a previously explained variable. In other words, after a reference is explained for a particular variable, using its original name as well as the reference can refer to the variable. Hence, a reference is nothing but an alias.

 Thus not passing a copy (call by value) saves time and is efficient. It does not have to make a temporary variable /. And not passing the address(call by address), eliminates the use of pointers in the called functions. But, at the same time, the changes made to a formal variable , using its reference or alias can be reflected back in the calling function.

 


Related Discussions:- Explain call by reference

Implement binary heap in c++?, A:BinaryHeap.h ------------ #ifndef BI...

A:BinaryHeap.h ------------ #ifndef BINARY_HEAP_H_ #define BINARY_HEAP_H_ #include "dsexceptions.h" #include "vector.h" // BinaryHeap class // CONSTRUCTION: wi

Control structures in cpp, Control structures The control structures app...

Control structures The control structures appear in both structured programming languages as well as object oriented programming languages.  The three constructs used are: i)

Write a program to change the matrix program, Change the matrix program (pr...

Change the matrix program (program 3) slightly. Overload == operator to compare two matrices to be added or subtracted. i.e., whether the column of first and the row of second

Described container class?explain types of container class, A container cla...

A container class is a class which is used to hold objects in external storage and memory. A container class work as a generic holder. A container class contains a predefined behav

Which constructor gets called while i create an array of , Which constructo...

Which constructor gets called while I create an array of Fred objects?

C program for function of count the characters in each word, C Program for ...

C Program for FUNCTION OF COUNT THE CHARACTERS IN EACH WORD void count(char c[]); void main() {           char a[50];           int i=0;           clrscr();

Define bitwise-shift operators, Define Bitwise-Shift Operators? The shi...

Define Bitwise-Shift Operators? The shift operators perform suitable shift by operator on the right to the operator on the left. The right operator should be positive. The va

Program for single int parameter, Write a function that has a single int pa...

Write a function that has a single int parameter n and returns an int: 0 if n is negative, otherwise 1. You are not allowed to simply check the integer value, and should use the fu

Basics, conceptual difference between big o,big thete and big omega

conceptual difference between big o,big thete and big omega

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