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counter = counter + 1;

can be reduced to

counter += 1;

Here is the full set.

*= Multyply
/= Divide
%= Modulus
+= Add
-= Subtract
<<= Left Shift
>>= Right Shift
&= Bitwise AND
^= Bitwise Exclusive OR (XOR)
|= Bitwise Ixclusive OR

if expr1 and expr2 are expressions then

expr1 op= expr2 is equivalent to expr1 = expr1 op expr2

Logical and relational operators

Relational operators

Operators Meaning Examples
> greater than 2>3 (is 0) 6>4 (is 1) a>b
>= greater than or equal to 6>= 4 (is 1) x>= a
< less than 5<3 (is 0),
<= less than or equal to 5<= 5 (is 1) 2<= 9 (is 1)
== equal to 3 == 4 (is 0) a == b
!= not equal to 5 != 6 (is 1) 6 != 6 (is 0)

Logical operators

Operators Meaning Data types of the operands Examples
&& logical and 2 logic expressions 3<5&&4<6 (is 1) 2<1&&2<3 (is 0) a>b&&c<d
|| logical or 2 logic expressions 6 || 0 (is 1) 3<2 || 3<3 (is 1) x>= a || x == 0
! logical not 1 logic expression !3 (is 0) !(2>5) (is 1)

Bitwise operators

Operators Meaning Data types of the operands Examples
& Binary AND 2 binary numbers 0&0 (is 0) 0&1 (is 0) 1&0 (is 0) 1&1 (is 1) 101&110 (is 100)
| Binary OR 2 binary numbers 0 | 0 (is 0) 0 | 1 (is 0)1 | 0 (is 0) 1 | 1 (is 1)101 | 110 (is 111)
^ Binary XOR 2 binary numbers 0 ^ 0 (is 0) 0 ^1 (is 1)1 ^ 0 (is 1) 1 ^ 1 (is 0)101 ^ 110 (is 011)
<< Shift left 1 binary number a<<n (is a*2n) 101<<2 (is 10100)
>> Shift right 1 binary number a>>n (is a/2n) 101>>2 (is 1)
~ One's complement 1 binary number ~ 0 (is 1) ~ 1 (is 0)~ 110 (is 001)

Increment and decrement operators

Incrementing, decrementing and doing calculations on a variable is a very common programming task and C has quicker ways of writing the code. The code is rather cyptic in appearance.

The increment operator ++ adds 1 to its operand while the decrement operator - -subtract 1. We have frequently used ++ to increment variables, as in

if (c = = ’\n’) ++n;

The unusual aspect is that ++ and - - may be used either as prefix operators (before the variable, as in ++n) or postfix operators (after the variable, as in n++). In both cases, the effect is to increment n. But the expression ++n increments n before its value is used, while n++ increment n after its value has been used. This mean that in a context where the value is being used, not just the effect, ++n and n++ are different. For example, if n is 5, then

x = n++;

sets x to 5 but

x = ++n;

sets x to 6. In both cases, n becomes 6.

The increment and decrement operator can only be applied to variables; an expression like (i + j)++ is illegal.

Memory addressing operators

The five operators listed in the following table are used in addressing array elements and members of structures, and in using pointers to access objects and functions.

Operator Meaning Example Result
& Address of &x Pointer to x
* Indirection operator *p The object or function that p points to
[ ] Subscripting x[y] The element with the index y in the array x (or the element with the index x in the array y: the [ ] operator works either way)
. Structure or union member designator x.y The member named y in the structure or union x
-> Structure or union member designator by reference p->y The member named y in the structure or union that p points to

Type conversions

When an operator has operands of different types, they are converted to a common type according to a small number of rules. In general, the only automatic conversion era those that convert a narrower operand into a wider one without loosing information, such as converting an integer into floating point .

If there are no unsigned operands, the following informal set of rules will suffice:

If either operand is long double, convert the other to long double.

Otherwise, if either operand is double, convert the other to double.

Otherwise if either operand is float, convert the other to float.

Otherwise convert char and short to int.

Then if either operand is long, convert the other to long.

A char is just a small integer, so chars may be freely used in arithmetic expressions

Precedence of operators

Operators listed by type.

All operators on the same line have the same precedence. The first line has the highest precedence.

Level Operators Associativity
1 () [] . ->++ (postfix) – (postfix) ----->
2 ! ~ ++ (prefix) -- (prefix) - *&sizeof <-----
3 * / % ----->
4 + - ----->
5 <<>> ----->
6 <<=>>= ----->
7 == != ----->
8 & ----->
9 ^ ----->
10 | ----->
11 && ----->
12 || ----->
13 ?: <-----
14 = += -= <-----

Note:associate left to right

Questions & Answers

how can chip be made from sand
Eke Reply
are nano particles real
Missy Reply
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
has a lot of application modern world
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Introduction to computer science. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10776/1.1
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