UrbanPro

Learn C Language from the Best Tutors

  • Affordable fees
  • 1-1 or Group class
  • Flexible Timings
  • Verified Tutors

Search in

What is the difference between #define and constant in C?

Asked by Last Modified  

Follow 0
Answer

Please enter your answer

#define used to define a variable that is pre-processed(before compilation) where as constant is a keyword used to declare constant variable which cannot be varied
Comments

C/C++ & UNIX Shell Scripting Programmer & Tutor

#define is a preprocessor directive and is resolved/replaced before the compilation step. So that means if you have like #define PI 3.42 --- during pre-processing (before compilation) imagine as if the compiler actually does a FIND and REPLACE inside your code and finds PI and replaces it with 3.42....
read more
#define is a preprocessor directive and is resolved/replaced before the compilation step. So that means if you have like #define PI 3.42 --- during pre-processing (before compilation) imagine as if the compiler actually does a FIND and REPLACE inside your code and finds PI and replaces it with 3.42. So there is no way that you can change a value in the program. The constants on the other hand also remain constant throughout the program but hold the memory as well as are resolved at the run time. Let me know if that resolves your query or I can make you understand it the memory way. read less
Comments

Tuitions for Maths,Science

#define A B tells the preproccessor (a part of the compiler) to substitute B wherever it sees A in the code, and it does it before compiling the code. A const variable means that once the variable is set it can't be changed.
Comments

View 1 more Answers

Related Questions

what are type qualifiers in c language
The type qualifiers/modifiers in C language are used to alter the meaning of basic data types. These can be divided into 3 categories: 1. Size modifiers a. short (default) b. long 2. Sign modifiers a....
Mahesh
Who created C?
The C was primarily created by Dennis Ritchie, an American computer scientist, in the early 1970s while working at Bell Labs. C was designed as a system programming language, initially for building utilities...
Srinivasan
0 0
8
What is meant by high-order and low-order bytes?
Lower order and higher-order bytes are the terms used while computing calculations in a programming language. Usually, numbers are written from left to right. The left is the most significant bit, and...
Vishal
0 0
9
What is the most efficient way to store flag values?
A flag is a value used to make a decision between two or more options in the execution of a program. Efficiency in this case is a tradeoff between size and speed. The most memory-space efficient way to...
Deepak
0 0
6

Now ask question in any of the 1000+ Categories, and get Answers from Tutors and Trainers on UrbanPro.com

Ask a Question

Related Lessons

C for Begginers
C is an procedure oriented programming language. For any begginer the word program is new. Program: Set of instructions to be followed by machine or computer. Instruction Examples: Arithmetic instruction...

What Are IT Industries Performance Metrics?
1. Outstanding Expectation: Eligible to get Promotion easily and good salary hike. Always preferrable to go abroad. 2. Exceed Expectation: Can get Promotion as per schedule of company with good salary...

Do You Know How Is Size Of Structure Defined?
Size of the structure is defined based on multiplies of bigger data type member in the structure. Example: If a structure contains integer, char, short data type, then size of the Structure will be multiples...

Static and dynamic libraries
A library is a package of code that is meant to be reused by many programs. A static library (also known as an archive) consists of routines that are compiled and linked directly into your program. When...

Features Of C Language
Features of C language It is a robust language with rich set of built-in functions and operators that can be used to write any complex program. The C compiler combines the capabilities of an assembly...

Recommended Articles

Brilliant Academy is one of the reputed institutes for B.Tech tuition classes. This institute is specialised in delivering quality tuition classes for B.E, Engineering - all streams and Engineering diploma courses. Incorporated in 2012, Brillant Academy is a brainchild of Mr Jagadeesh. The main motto of the academy is to...

Read full article >

Lasya Infotech is a Hyderabad based IT training institute founded in 2016 by O Venkat. Believing in his innovation, passion and persistence and with a diverse blend of experience, he started his brainchild to deliver exemplary professional courses to aspiring candidates by honing their skills. Ever since the institute envisions...

Read full article >

Microsoft Excel is an electronic spreadsheet tool which is commonly used for financial and statistical data processing. It has been developed by Microsoft and forms a major component of the widely used Microsoft Office. From individual users to the top IT companies, Excel is used worldwide. Excel is one of the most important...

Read full article >

Applications engineering is a hot trend in the current IT market.  An applications engineer is responsible for designing and application of technology products relating to various aspects of computing. To accomplish this, he/she has to work collaboratively with the company’s manufacturing, marketing, sales, and customer...

Read full article >

Looking for C Language Classes?

Learn from the Best Tutors on UrbanPro

Are you a Tutor or Training Institute?

Join UrbanPro Today to find students near you
X

Looking for C Language Classes?

The best tutors for C Language Classes are on UrbanPro

  • Select the best Tutor
  • Book & Attend a Free Demo
  • Pay and start Learning

Learn C Language with the Best Tutors

The best Tutors for C Language Classes are on UrbanPro

This website uses cookies

We use cookies to improve user experience. Choose what cookies you allow us to use. You can read more about our Cookie Policy in our Privacy Policy

Accept All
Decline All

UrbanPro.com is India's largest network of most trusted tutors and institutes. Over 55 lakh students rely on UrbanPro.com, to fulfill their learning requirements across 1,000+ categories. Using UrbanPro.com, parents, and students can compare multiple Tutors and Institutes and choose the one that best suits their requirements. More than 7.5 lakh verified Tutors and Institutes are helping millions of students every day and growing their tutoring business on UrbanPro.com. Whether you are looking for a tutor to learn mathematics, a German language trainer to brush up your German language skills or an institute to upgrade your IT skills, we have got the best selection of Tutors and Training Institutes for you. Read more