[tutorial] Basics Of C Programming - Part 2

[dhanesh1405241511 0]

Ok, well here is the Second part of the tutorial i promised.

 

Operators & Expressions in C

 

Introduction

 

In c the variable, arrays or function references are combined with operators to form expressions.

Eg. C=A+B

The data items that the operators act upon are called operands.

Some operators require two operands will others require just a single operand to act upon.

Types Of Operators :

 

Arithmetic Operators

Unary Operators

Relational and Logical Operators

Assignment Operators

Conditional Operators

Arithmetic Operators

 

+ : Addition

: subtraction

* : Multiplication

/ : Division

% : Modulus

The operands must represent numeric values

Eg : Integer, Floating, or characters – C character set

% : Both operands must be integer and second one nonzero.

/ : Second operand must be a Nonzero.

Both operands are integers then referred to as integer division

Operation is carried by two floating values then Floating point division.

If one integer and the other float then the result will be floating quotient.

Type Cast : Converts the value of an expression to a required data type if needed.

Syntax ( Data type) Expression

Eg. ((int)%4

 

Unary Operator:

 

They act upon a single operand to produce a new value.

Types :

Increment Operator

++ : Increments the value in the operand by 1

Eg: ++a, a++

Decrement Operator

--: Decrements the value in the operand by one

Eg. : --a, a--.

sizeof : returns the size of the operand in terms of bytes. And is always preceded by its operand.

Eg. Printf( “THE SIZE OF VARIBALE A IS : %d”, sizeof a);

 

 

Relational and Logical Operator:

Relational Operators :

<= : Less than or equal to

>= : Greater than or equal to

> : Greater than

< : Less than

== : Equal to

!= : Not Equal to

Logical Operators :

&& - and : Both the conditions should hold true

|| - or : Either one of the condition should hold true for the action to be performed.

Assignment Operators :

They are used to form an assignment expression

It would assign a value of an expression to a identifier.

Types :

=

+=

-=

*=

/=

%=

Conditional Operator :

Used for carrying out conditional operations – ( ? : )

Syntax : Expression 1 ? Expression 2 : Expression 3

Eg. i=10

ans= (i<=10) ? 0 : 1

 

Yeap, well that wraps up the Conditional Operators topic. As suggested, i would post some examples of code later on, but till then you could go through these basic guidelines and perfect them. Hope this helped

 

Regards

Dhanesh.

 

[Omkar™ 0]

Alright, that did make a great Part II, and you didn't screw up any code this time either! Good work, but you missed out some things (Of course you can't teach C Prog. in 2 parts ) so I'd write Part III, if I get time, that is! No, really - I'm working hard on my website right now, and filling up my forums too!

 

Honestly, you should be adding some examples and some assignments too, as a good tutor!!!

Edited July 28, 2006 by Omkar™ (see edit history)

[dhanesh1405241511 0]

LOL omkar .. true but hard to believe, I'll kill someone if they dont understand what i teach .. lol . I am a really impatient tutor. Guess i have to be working on my teaching skills from now. hehe .. As for Part 3 .. Its all yours, really .. I havent started yet .. so whenever you get time .. go on and complete whatever i have missed out. Its not easy to complete C in 2 parts true, so i hope you will add up a few pointers for us then .. Thankx for your comments.RegardsDhanesh.

[cyborgxxi 0]

Hey DhaneshLong time no see, digital brother. <LOLWow I am just amazed at how much you guys are literate in computer programming languages. For me, it's HTML and I only know the basics. Well, it's kinda sad but I guess it can hold out for a little time being while I go try to learn PHP.Can someone answer my question:How can you benefit from being literate in C programming and C++?? What about C++ Visuals? Is that another programming language too?By the way, wonderful job there, Dhanesh. Kudos for you.

[dhanesh1405241511 0]

Hey Dhanesh

Long time no see, digital brother. <LOL

 

Aha .. the Hobbes of asta .. long time indeed, where have u been bro and how've you been ?. Seems like you were bz with ur website. Best of luck for that share it with us sometime ..

Can someone answer my question:

 

How can you benefit from being literate in C programming and C++?? What about C++ Visuals? Is that another programming language too?

 

I think the best people to answer this would be people who are INTO programming. But lets see, by learning C / C++ which are the foundation of any programming languages today, you would be able to design/program applications flexibly. Visual C++ is a form of basic command C/C++, just with a pretty GUI and with the title of M$, i have seen people who prefer the basic C/C++ more to the Visual C++. One major difference would be the syntax, Different programming languages have different syntax, but its easy to cope up when you are fluent with 1 basic language.

 

I love to work on Visual Basic, and to be honest, i have to be changing that, cause tho VB might seem easy with GUI and stuff, its not so flexible as command C/C++ ..Hope you get the basic point .. Anyone else who can elaborate on this is welcome ..

 

Hope you see more of you around Hobbes ... lol

Regards

Dhanesh.

[iGuest 3]

These are old knowledge... I miss them sooo!!

[yordan 10]

Honestly, you should be adding some examples

I agree.Mainle, I see what ++i is (it changes i to i+1).
I would like to know what += means. if a=-1, += applied to a makes it change to -2 or to 0 ?

[evion 0]

Hey Dhanesh, hobbes , long time no see.

 

I've been studying Visual Basic for the past few weeks now as a course in school. It's getting a little more complicated now that i've moved up to ifs and elses. Some of the operators i see used in C (as you have portrayed) is really similar to that of Visual Basic, one difference i can point out though, is how to make equations equal, that is using the double equal sign (==). It reminds me of back when i was studying a little php. They say that Visual Basic is a good base before moving on to other languages such as C or C pluses, it doesn't seem so at first glance, and if you know me, I'm not a very good reading learner .

 

Going out of the topic for a moment. The book we're using in our Visual Basic course describes something about pseudocode. Where you actually incorporate understandable English language as code. A friend told me it is just a form of "laying out" your code into more understandable parts. But I'm wondering if pseudocode actually works as a language itself?

[SP Rao 0]

It was a good tutorial indeed. Though I did find some omissions. 1)First you didn't differntiate between a++ and ++a. May be you have a plan of explaining it later.2) You have left out bitwise operators completely. (Operators like XOR-^ , OR- | , AND - & , NOT - ~ ). In fact along with the assignment operators you've mentioned, the following also hold good.|=, &=,^=. 3)Also, there are bitshift operators. Bitwise left shift (<<) and bitwise right shift(>>) operators whih help in doing bitshifting operations.Once again I repeat I'm not sure if you have plans of covering these in your next part. But if you didn't have such plans, you can include these in your next part of the tutorial

Edited October 19, 2006 by SP Rao (see edit history)

[Chesso 0]

It looks like a great piece of information to me, Iv'e done DLL's and things in C++ and still didn't know some of that .

[SP Rao 0]

It looks like a great piece of information to me, Iv'e done DLL's and things in C++ and still didn't know some of that .

May be bacause you never needed BITWISE operators... They are very much useful in embedded system programming and system programming.

For high level codes, BITWISE operators may not be necessary. (I've never done any DLL's. So ain't sure if you do BIT operations there... All I know about DLL is it stands for Dinamic Link Libraries. Atleast thet's what I think it is )

[PS: Sorry for late response. Didn't come online for a long time as I was caught up with series of unfortunate events. Finally I'm free!!! ]

[bluefish1405241537 0]

I agree.Mainle, I see what ++i is (it changes i to i+1).
I would like to know what += means. if a=-1, += applied to a makes it change to -2 or to 0 ?

Here is an example:
a = 10;
a += 1;
(a==11);
a = 0;
a += -1;
(a==-1);
a = 5;
a += -3;
(a==2);

So a += b; is the same as writing a = a + b;, just a simpler syntax.

[yordan 10]

Here is an example:a = 10;
a += 1;
(a==11);
a = 0;
a += -1;
(a==-1);
a = 5;
a += -3;
(a==2);

So a += b; is the same as writing a = a + b;, just a simpler syntax.

OK, thanks for the reply. I learned something today, now I know what "+=" means.

[Chesso 0]

I actually didn't know what it meant either, but I don't think I have ever needed to use it, but then again Iv'e only seen it used rarely.

[yordan 10]

I actually didn't know what it meant either, but I don't think I have ever needed to use it, but then again Iv'e only seen it used rarely.

rarely is already a lot. I never saw thins += thing until today, and I don't even mind seeing somebody using it. Nevertheless, from a philosophical point of view, knowledge is supposed to be a good thing, even for (probably) useless things