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

What are arrays, What are Arrays? Numerous applications require the pro...

What are Arrays? Numerous applications require the processing of multiple data items that have identical characteristics. In such circumstances it is frequently convenient to p

Built a web crawler , To develop a web crawler such that when given a base ...

To develop a web crawler such that when given a base URL, it will traverse the entire web tree and then build an index of keywords and what URL link they appear on.   The web crawl

Write a c program to input a floating point number, Step 1 Define the start...

Step 1 Define the start of the program    It should be noted that within C all commands should end in a semi-colon. For most of your programs the definition of a program header as

What is threaded binary tree, Threaded binary tree: Consider the linked il...

Threaded binary tree: Consider the linked illustration of a binary tree 'T.  Approximately half of the entries is the pointer fields 'LEFT' and 'RIGHT' will have null elements. Th

Friends of classes, Define the following Window class : - integer  data mem...

Define the following Window class : - integer  data members, width and height - a constructor  that accepts two integer  parameters  (width followed by height) and uses them to ini

Program to calculate students marks, #include using namespace std; void...

#include using namespace std; void print(int marks_arr[],int cnt) { int ind[cnt]; int i=0; int j=0; int k=0; int s=0; for(k=0;k { ind[k]=0; } int cnt1=0; for(i=0;i

String function examples, 1. De ne a function chomp :: String -> String tha...

1. De ne a function chomp :: String -> String that selects a run of repeated characters from the start of a string with the run being as long as possible. For example ch

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

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 between two points can b

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

Develop stocastic expert advisor, Project Description: Need to develop a...

Project Description: Need to develop an expert advisor base on sthocastic oscilator with my own setting.. Very basic touch line OB/OS only but on my setting n condition Skill

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