Explain the #undef directive, C/C++ Programming

Assignment Help:

The #undef Directive

This directive undefines a previously explained macro. For, example the following will give an error since PI is undefined.

                #define PI 3.14285

                void main()

                 {

                                cout<< PI;                                           // no error here

                  # undef PI;

 

cout << PI;                          // error after undef.

                 }

 


Related Discussions:- Explain the #undef directive

Program to draw a circle - c program, Program to draw a circle: int ma...

Program to draw a circle: int main(void) {    /* request auto detection */    int gdriver = DETECT, gmode, errorcode;    int midx, midy;    int radius = 100;

C program for swapping the string, C Program for SWAPPING THE STRING #i...

C Program for SWAPPING THE STRING #include conio.h> #include stdio.h> void main() {           char a[50],temp=0;           int i=0,c=0,c1=0,l=0;           clr

What is the main advantage to using a data file, Problem: (a) What is ...

Problem: (a) What is the main advantage to using a data file? (b) What is meant by opening a data file? How is this accomplished? Illustrate your answer clearly with a sui

Program of file data, Program of file data: FileData::FileData( ffblk&...

Program of file data: FileData::FileData( ffblk& blk ) :     fileName( blk.ff_name ),     fileDate( (blk.ff_fdate >> 5) & 0x000F,               blk.ff_fdate & 0x0001F

Matematic, how to make program c++

how to make program c++

Define an asset base class, a) Define an Asset base class that provides the...

a) Define an Asset base class that provides the following method: class Asset { public:      virtual double getValue()=0; };   This will be the base class for both stock an

Create a stack using arrays, Problem : (a) Stacks can be implemented u...

Problem : (a) Stacks can be implemented using arrays. Write down the following C or C++ function to (i) create a stack (ii) add an element to a stack (push). (b) Expl

Functions, Define  F u n c t i o n?  T h e r e a r e t...

Define  F u n c t i o n?  T h e r e a r e t w o t y p e s o f f u n ct i o n b u i l t - i n f un ct i o n s a n d u

Help me for an programming contest .., Pebble Merchant Problem Description...

Pebble Merchant Problem Description There is a pebble merchant. He sells the pebbles, that are used for shining the floor. His main duty is to take the length of the room’s sides

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