An operator is a symbol that tells
the compiler to perform specific mathematical or logical functions. C language
is rich in builtin operators and provides the following types of operators −
 Arithmetic Operators
 Relational Operators
 Logical Operators
 Bitwise Operators
 Assignment Operators
 Misc Operators
We will, in this chapter, look into
the way each operator works.
Arithmetic
Operators
The following table shows all the
arithmetic operators supported by the C language. Assume variable A
holds 10 and variable B holds 20 then −
Operator

Description

Example

+

Adds two operands.

A + B = 30

−

Subtracts second operand from the
first.

A − B = 10

*

Multiplies both operands.

A * B = 200

/

Divides numerator by denumerator.

B / A = 2

%

Modulus Operator and remainder of
after an integer division.

B % A = 0

++

Increment operator increases the
integer value by one.

A++ = 11



Decrement operator decreases the
integer value by one.

A = 9

Relational
Operators
The following table shows all the
relational operators supported by C. Assume variable A holds 10 and
variable B holds 20 then −
Operator

Description

Example

==

Checks if the values of two
operands are equal or not. If yes, then the condition becomes true.

(A == B) is not true.

!=

Checks if the values of two
operands are equal or not. If the values are not equal, then the condition
becomes true.

(A != B) is true.

>

Checks if the value of left
operand is greater than the value of right operand. If yes, then the
condition becomes true.

(A > B) is not true.

<

Checks if the value of left
operand is less than the value of right operand. If yes, then the condition
becomes true.

(A < B) is true.

>=

Checks if the value of left
operand is greater than or equal to the value of right operand. If yes, then
the condition becomes true.

(A >= B) is not true.

<=

Checks if the value of left
operand is less than or equal to the value of right operand. If yes, then the
condition becomes true.

(A <= B) is true.

Logical
Operators
Following table shows all the
logical operators supported by C language. Assume variable A holds 1 and
variable B holds 0, then −
Operator

Description

Example

&&

Called Logical AND operator. If
both the operands are nonzero, then the condition becomes true.

(A && B) is false.



Called Logical OR Operator. If any
of the two operands is nonzero, then the condition becomes true.

(A  B) is true.

!

Called Logical NOT Operator. It is
used to reverse the logical state of its operand. If a condition is true,
then Logical NOT operator will make it false.

!(A && B) is true.

Bitwise
Operators
Bitwise operator works on bits and
perform bitbybit operation. The truth tables for &, , and ^ is as
follows −
p

q

p
& q

p
 q

p
^ q

0

0

0

0

0

0

1

0

1

1

1

1

1

1

0

1

0

0

1

1

Assume A = 60 and B = 13 in binary
format, they will be as follows −
A = 0011 1100
B = 0000 1101

A&B = 0000 1100
AB = 0011 1101
A^B = 0011 0001
~A = 1100 0011
The following table lists the
bitwise operators supported by C. Assume variable 'A' holds 60 and variable 'B'
holds 13, then −
Operator

Description

Example

&

Binary AND Operator copies a bit
to the result if it exists in both operands.

(A & B) = 12, i.e., 0000 1100



Binary OR Operator copies a bit if
it exists in either operand.

(A  B) = 61, i.e., 0011 1101

^

Binary XOR Operator copies the bit
if it is set in one operand but not both.

(A ^ B) = 49, i.e., 0011 0001

~

Binary Ones Complement Operator is
unary and has the effect of 'flipping' bits.

(~A ) = 61, i.e,. 1100 0011 in
2's complement form.

<<

Binary Left Shift Operator. The
left operands value is moved left by the number of bits specified by the
right operand.

A << 2 = 240 i.e., 1111 0000

>>

Binary Right Shift Operator. The
left operands value is moved right by the number of bits specified by the
right operand.

A >> 2 = 15 i.e., 0000 1111

Assignment
Operators
The following table lists the
assignment operators supported by the C language −
Operator

Description

Example

=

Simple assignment operator.
Assigns values from right side operands to left side operand

C = A + B will assign the value of
A + B to C

+=

Add AND assignment operator. It
adds the right operand to the left operand and assign the result to the left
operand.

C += A is equivalent to C = C + A

=

Subtract AND assignment operator.
It subtracts the right operand from the left operand and assigns the result
to the left operand.

C = A is equivalent to C = C  A

*=

Multiply AND assignment operator.
It multiplies the right operand with the left operand and assigns the result
to the left operand.

C *= A is equivalent to C = C * A

/=

Divide AND assignment operator. It
divides the left operand with the right operand and assigns the result to the
left operand.

C /= A is equivalent to C = C / A

%=

Modulus AND assignment operator.
It takes modulus using two operands and assigns the result to the left operand.

C %= A is equivalent to C = C % A

<<=

Left shift AND assignment
operator.

C <<= 2 is same as C = C
<< 2

>>=

Right shift AND assignment
operator.

C >>= 2 is same as C = C
>> 2

&=

Bitwise AND assignment operator.

C &= 2 is same as C = C &
2

^=

Bitwise exclusive OR and
assignment operator.

C ^= 2 is same as C = C ^ 2

=

Bitwise inclusive OR and
assignment operator.

C = 2 is same as C = C  2

Misc
Operators ↦ sizeof & ternary
Besides the operators discussed
above, there are a few other important operators including sizeof and ?
: supported by the C Language.
Operator

Description

Example

sizeof()

Returns the size of a variable.

sizeof(a), where a is integer,
will return 4.

&

Returns the address of a variable.

&a; returns the actual address
of the variable.

*

Pointer to a variable.

*a;

? :

Conditional Expression.

If Condition is true ? then value
X : otherwise value Y

Related Articles:
Operators Precedence in C  