P K Subudhi

What is the main difference between returning value of a function and does not return any value of a function in  C. Which is correct void main(void), int main(void), int main(int) , or void main(int) and explain the main difference between int main() and int main(void). 

The data-type keyword (including void) used just before the function-name indicates whether the function returns or not. If a function is void then it does not return anything, if any other data-type is return then it returns a value of that specified data-type. Question is that how can we know which function return and which won't? I can give a simple example. Let us consider you are a function who is master in calculating Factorial, and, I want to calculate factorial of an integer, that I am giving to you to calculate. right? Tell me whether you will give me something or not? Yes indeed you have to return me calculated result. Here the function is returnable. Now in the same way I am another task, "I said you to wear Red dress if it is Sunday, Blue on Monday, Green on Tue etc" Rigth? So here what will you return me? Nothing! You will do that but you have nothing to return. So here the function would be "void" (Non-Returnable). In this way you have to understand where a function returns and where it won't.

There is no rule, concept or technique (to be explained) for your requirement, however logic development is a gradual process. You can progrees with time. I can say here that if you have thrre things in your mind then you can win 1. Interest (Sradha) 2. Dedication (Lagan) 3. Learning Attitude. Go from basic and dream upto the last. Enjoy your work (let it be a silly one). To develop logic you have to understand like you are the end-user and you have to find out the logic flow (step by step).

You need two things; 1. Your deep interest and 2. Your dedication. You can be master by practice. If you give me 1 year time then I can start from C, and then C++, Java and .NET (C#.NET, ASP.NET, ADO.NET, HTML/CSS) etc. and then you will be a professional programmer with the subjects that is in trend. See learning what are there in a programming language is not enough, you have to practice more case studies every day to tame the language...

To be master in C, you have to pick fundamental books at first and then you have to refer books with advanced concepts. Let Us C (By Yashwant Kanitkar) is good fundamental book but Moolish Cooper, Dennis Ritchie, Venugopal like authors also written advanced topics. Anyhow you will find few new things in different books. Kanitkar also written books like Graphics in C, Undocumented DOS programming in C etc are also excellent one

Frankly C++ is the super-set of C Language. If one knows C++ indicates he has knowledge of C as well. However programming pattern of C is solely structured programming but C++ supports object oriented. Bjerne Stroustrup when he designed C++, initially he has named it as C with Classes. By this you can judge that C++ is just an extended version of C, that is why it is named as C and plus and plus (kind of incremented). NOTE that everything that you have in C can be used in C++ in the same way (with few modification).