Operators :
C supports a rich set of operators. An
operator is a symbol that tells the computer to perform certain mathematical or
logical manipulations. C is classified into number of categories. They are :
1.
Arithmetic Operators.
2.
Relational Operators.
3.
Logical Operators.
4.
Conditional Operators.
5.
Bitwise Operators.
7.
Assignment Operator.
8. Increment and Decrement Operators.
1. Arithmetic
Operators :
Arithmetic operators are used
for arithmetic operations like addition, subtraction, division etc.. They are
mainly 5 arithmetic operators used in C language.
They are :
1. * Multiplication
2. / Division
3. % Modulus
4. + Addition
5.
-
Subtraction
Ex
: a=8, b=4 then a + b = 12
a – b = 4
a * b = 32
a / b = 2
a % b = 0
Arithmetic Operators are further classified into 3 types.
They are :
1.
Integer Arithmetic Expression
2.
Real or Float Arithmetic Expression
1.
Mixed mode Arithmetic Expression
1. Integer
Arithmetic Expression:
When both operands are of integer type
then such type of expression
using arithmetic operators is called
Integer Arithmetic Expression.
Ex
: 3+2, 3-2, etc.
2. Real
or Float Arithmetic Expression :
When both the operands are of real type then such type of
expression using arithmetic operators is called Real or Float Arithmetic
Expression.
Ex
: 1.2+2.1, 3.2*1.2
etc…
3.
Mixed mode Arithmetic Expression :
When one
operand is of integer type and other is of real type then such expression using arithmetic
operators is called Mixed mode Arithmetic Expression.
Ex : 1.2+3 ,
3*1.2 , etc.
2. Relational Operator :
Relational
Operators are used to create a relationship among the operands. They
are used for comparison purpose. . It is
in the form as
Operand1 operator
operand2;
The value of a
relational expression is either 1 or 0 depending on relation either true or
false. These are used in mostly decision making and branching statements, and
looping statements.
C supports 6 relational operators. They are :
1. < Less Than
2. > Greater Than
3. <= Less than and equal to
4. >= Greater than and equal to
5. == Equal to
6.
!= Not equal to
Ex : If a=5 b=3, then the various
relational expressions would be as follows :
Relational
Expression Result
a>b true
a<b false
a<=b false
a>=b false
a==b false
a!=b true
3. Logical Operators :
The logical operators are used to combine or
construct compound conditional expressions and also to negate expressions.
These are used in decision-making statement and some looping statements like
if, switch ,while , etc. These statements have either true(1) or false(0).
C supports 3 types of logical operators.
They are :
1. Logical
AND (&&)
2. Logical
OR (||)
3. Logical
NOT (!)
1. Logical
AND (&&) :
In Logical AND operator if both
operands(expressions)are true then the result will be true i.e. 1 otherwise the
result will be false i.e. 0. The general syntax for logical AND operator using
the symbol && is
op1 && op2
The truth table for Logical AND
operator is shown below
Op1
|
Op2
|
Op1 && Op2
|
0
|
0
|
0
|
1
|
0
|
0
|
0
|
1
|
0
|
1
|
1
|
1
|
2. Logical
OR (||) :
In
Logical OR operator if any one of the operand(expression)is true then the
result will be true i.e. 1 otherwise the result will be false i.e. 0. The
general syntax for logical OR operator using the symbol || is op1 || op2
The truth table for Logical OR operator
is shown below
Op1
|
Op2
|
Op1|| Op2
|
0
|
0
|
0
|
1
|
0
|
1
|
0
|
1
|
1
|
1
|
1
|
1
|
3. Logical NOT (!) :
The logical NOT operator gives the
negation of an operand(expression). The general syntax for Logical NOT operator
using the symbol ! is !op
Op
|
!Op
|
1
|
0
|
0
|
1
|
4. Conditional Operator :
Conditional operators are also
called Ternary operator. These operators are used instead of “ if ” statement.
The syntax for conditional operator is :
exp1
? exp2 : exp3 ;
Here first the expression exp1
will be computed which is a conditional expression. If exp1 is true then exp2
will be executed. But if exp1 is false then exp3 will be executed.
Ex
: c=(a>b)?a-b:a+b;
if
a=5 and b=4 then according to the conditional operator
c=(5>4)?5-4:5+4;
c=1 ( as 5 is greater
than 4 so exp2 is executed i.e. 5-4=1 )
5. Bitwise Operator :
Bitwise
operators are specially used for low level programming. These operators are
used for the manipulation of binary data i.e. bits. These operators should not
be of float or double type. C supports 6 types of Bitwise operators.
They
are :
1.
Bitwise AND ( & )
2.
Bitwise OR (| )
3.
Bitwise Exclusive OR
( ^ )
4.
Bitwise Shift Left (
<< )
5.
Bitwise Shift Right (
>> )
6.
Bitwise Complement(bitwise NOT) (
~ )
1. Bitwise AND
(&):
AND operator is a binary
operator which needs two operands to operate.
AND operator operates by adding the individual bits of two operands one
by one. If both operand has 1 at same position then the result is 1 otherwise
the result is 0.
Ex
: Let a = 00101010
b = 10011001
then
c = a & b = 00001000
2. Bitwise OR (|):
OR operator is a binary
operator which operates on two operands. If any one of the bit value is 1 then
it results to 1 otherwise 0.
Ex
: Let a = 00101010
b = 10011001
then c = a | b = 10111011
3. Bitwise Exclusive
OR (^):
Exclusive OR is a
binary operator which operates on two operands. This operator returns 1 if one
operand has the bit value 1 and the other has 0 at same position or vice-cersa
otherwise it returns 0.
Ex
: Let a = 00101010
b = 10011001
then c = a ^ b = 10110011
4. Bitwise Shift Left
(<<):
Bitwise
shift left operator transfer the bits of data to left side. The left operand is
the data and the right operand is the no. of times the shift operation is to be
done. Here the most significant bit will be discarded and the least significant
bit will come out to be 0.
The
syntax is : op << n
Ex : x = 0100
1001 1100 1011
X << 3 = 0100 1110 0101 1000
5. Bitwise Shift Right (>>) :
Bitwise shift right operator
transfers the bits of data to right side. The left operand is the data and the
right operand is the no. of times the shift operation is to be done. Here the
least significant bit will be discarded and the most significant bit will come
out to be 0.
The syntax is op >>
n
Ex : x = 0100 1001 1100 1011
X
>> 3 = 0000
1001 0011 1001
6. Bitwise Complement (bitwise NOT)(~) :
One’s
complement operator is a unary operator which is similar to NOT. It converts 0
to 1 and 1 to 0.
Ex : Let a = 5
it’s binary equivalent is a= 00000101
~a=
11111010
6.
Comma Operator :
When
number of statements occur in a C program having a relationship between
expressions, then we can write all expressions or statements in a single
expression using the comma operator.
Mostly
the comma operator is used in looping statements like while, do-while and for.
EX : a=12;
b=10;
c=a+b;
So, the above statement can be
written as c=(a=12,b=10,a+b);
Type Operator :
Type operator is used for
conversion purpose or casting purpose. So it is also called convert operator.
This operator converts float type data into integer form and vice-versa. It is
also used for casting a value and process to convert from one form to another
is called Casting.
The syntax is:
(type) v or
e;
Ex:
int a,b;
float c;
a=5;
b=2;
c=a/b;
If
we divide a by b, then result stored in the C variable be 2.0. But by using the
type operator, we can get the float value as:
c=(float)a/b;
7. Assignment Operator :
Assignment operator s are used for assigning an
expression or value to a variable. Assignment operators are further divided
into two types. They are
·
Simple Assignment Operator
·
Shorthand Assignment Operator
(or)
Arithmetic Assignment Operator
Simple Assignment Operator :
Simple
assignment operator is = (equal to). The general syntax
of simple assignment operator is :
V=constant
value (or) variable (or) expression;
Ex: a=3;
b=c;
Shorthand Assignment (or) Arithmetic Assignment Operator:
These operators
have = (equal to) sign with all arithmetic
operators. The general syntax is :
v arithmetic operator
= constant value or expression;
where v is the variable and
expression can be an arithmetic expression i.e.+,-,/,*,%.
Ex: Simple Assignment Shorthand Assignment
i=i+1; i+=1;
a=a*b+c; a*=b+c;
b=b%c; b%=c;
8. Increment/Decrement Operator:
These operators are
also called unary operators. Another name for increment and decrement operators
is counter operator. Increment Operator (++ ) are used for incrementing the
value by 1 and Decrement Operator( -- )
is used for decrementing the value by 1. These operators are further
divided into types. They are
·
Prefix Increment/Decrement
·
Postfix Increment/Decrement
Prefix
Operator :
In the prefix increment operator first of
all value will be incremented and then incremented value will be assigned to a
variable. Similarly in the prefix decrement operator first of all the value
will be decremented and then decremented value be assigned to the variable.
They are represented as :
++v; prefix increment
--v; prefix decrement where
v is the variable.
Postfix
Operator :
In the postfix increment
operator first of all value will be assigned to a variable and then value will
be incremented. Similarly in the postfix decrement operator first of all the
value will be
assigned
to a variable and then value will be decremented.
They are represented as :
v++; postfix increment
v--; postfix decrement where v is the variable.
Ex: x=7 x=7
Y=++x y=x++
After
processing : After processing :
Value of y is 8 value of y=7
Value of y is 8
value of x=8
x=7 x=7
Y=--x y=x--
After
processing : After processing :
Value of y is 6 value of y=7
Value of y is 6 value of x=6
Order
of Operators Precedence :
Order
of precedence means the rank in which all the operators operate in a C
expression. The order of precedence and associatively between these operators
is shown below :
Operator
|
Description
|
Associatively
|
Rank
|
()
|
Parenthesis
|
Left
to right
|
1
|
[]
|
Square
bracket
|
Left
to right
|
1
|
+
|
Unary
plus
|
Right
to left
|
2
|
-
|
Unary
minus
|
Right
to left
|
2
|
++
|
increment
|
Right
to left
|
2
|
--
|
Decrement
|
Right
to left
|
2
|
!
|
Logical
negation
|
Right
to left
|
2
|
~
|
One’s
compliment
|
Right
to left
|
2
|
*
|
indirection
|
Right
to left
|
2
|
&
|
Address
|
Right
to left
|
2
|
Size
of
|
Size
of an object
|
Right
to left
|
2
|
(type)
|
Type
cast
|
Left
to right
|
2
|
*
|
multiplication
|
Left
to right
|
3
|
/
|
Division
|
Left
to right
|
3
|
%
|
modulus
|
Left
to right
|
3
|
+
|
Addition
|
Left
to right
|
4
|
-
|
subtraction
|
Left
to right
|
4
|
<<
|
Left
shift
|
Left
to right
|
5
|
>>
|
Right
shift
|
Left
to right
|
5
|
<
|
Less
than
|
Left
to right
|
6
|
<=
|
Less
than or equal to
|
Left
to right
|
6
|
>
|
Greater
than
|
Left
to right
|
6
|
>=
|
Greater
than or equal to
|
Left
to right
|
6
|
==
|
equality
|
Left
to right
|
7
|
!=
|
inequality
|
Left
to right
|
7
|
&
|
Bitwise
AND
|
Left
to right
|
8
|
^
|
Bitwise
XOR
|
Left
to right
|
9
|
|
|
Bitwise
OR
|
Left
to right
|
10
|
&&
|
Logical
AND
|
Left
to right
|
11
|
||
|
Logical
OR
|
Left
to right
|
12
|
?!
|
Conditional
operator
|
Right
to left
|
13
|
=
|
Assignment
operator
|
Right
to left
|
14
|
,
|
Comma
operator
|
Left
to right
|
15
|
