Wednesday, 27 February 2013

Discuss the different types of operators used in C with an example for each

C supports a rich set of operators. They are classified into following categories:
1.            Arithmetic operators
2.            Relational operators
3.            Logical operators
4.            Assignment operators
5.            Increment and decrement operators
6.            Conditional operators
7.            Bitwise operators
8.            Special operators(Comma ‘,’ and sizeof() operator)


Ø    Arithmetic operators:  C provides all the basic arithmetic operators which are following:
           
Operator
Description
Example
+
Addition or unary plus
5+4 Result 9
-
Subtraction or unary minus
5-4 Result 1
*
Multiplication
5*4  Result 20
/
Division
5/4 Result 1
%
Modulo division
5/4 Result 1


Ø    Relational operators:

C provides all the basic relation operators to compare two or more quantities and depending on their relation taking decision. These operators and their meanings are as below.

Operator
Description
Example
greater than
5 > 4
>=
greater than or equal to
mark >= score
less than
height < 75
<=
less than or equal to
height <= input
==
equal to
score == mark
!=
not equal to
5 != 4


Ø    Logical operators:

In addition to the relational operators, C has the following three logical operators. The logical operators && and || are used when we want to test more than one condition and make decision.

Operator
Description
Example
&&
Logical AND
If(1< i &&  I <10)  ...
||
Logical OR
If (i <5 || I =5) ...
!
Logical NOT
If ( i !=5) ...

Ø    Assignment operators:

Assignment operators are used to assign the result of an expression to a variable.

Operator
Description
Example
=
Assignment Operator
a= 5


Ø    Increment and decrement operators(Or Binary Operator):

C provides shortcuts to add or subtract constant 1 to a variable.

Operator
Description
Example
++
Increment
a=a++
--
Decrement
a=a--


Ø    Conditional operators:

The conditional operator (ternary operator) pair “?:” is available in C to construct conditional expressions of the form
            Expr1?expr2:expr3
For example
a=100;
b=200;
c=(a>b)?a:b;
Result: c=200
This is same as if..else statement as follows:
if (a>b)
            c=a;
else
            c=b;


Ø    Bitwise operators:

The bitwise operators operate on integers thought of as binary numbers or strings of bits. These operators let us work with the individual bits of a variable; one common use is to treat an integer as a set of single-bit flags.

Operator
Description
Example
&
Bitwise AND

|
Bitwise OR

^
Bitwise exclusive OR

<< 
Shift left

>> 
Shift right



Ø    Special operators:

C supports some special operators like ‘,’ and sizeof() operators.
The ‘,’ (comma) operator can be used to link the related expression together.
The sizeof() is a compile time operator and, when used with an operand it returns the numbers of bytes the operand occupies. The operand may be variable, a constant or a data type qualifier.

Operator
Description
Example
,
Comma Operator
Value=(x=10, y=5, x+y) Results: value=15
sizeof()
Sizeof() Operator
k= sizeof(235L)