1. Operators and Expressions
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2. Introduction
• An operator indicates an operation to be
performed on data that yields a new value.
• An operand is a data items on which operators
perform operations.
• C provides rich set of “Operators”
– Arithmetic
– Relational
– Logical
– Bitwise
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3. Introduction
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4. Properties of Operators
• Precedence
– Precedence means priority.
– When an expressions contains many operators,
the operations are carried out according to the
priority of the operators.
– The higher priority operations are solved first.
– Example
• 10 * 5 + 4 / 2
• 10 + 5 – 8 * 2 / 2
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5. Properties of Operators
• Associativity
– Associativity means the direction of execution.
– When an expression has operators with same precedence, the associativity
property decides which operation to be carried out first.
a) Left to Right : The expression evaluation starts from the left to right direction
Example : 12 * 4 / 8 % 2
48 / 8 % 2
6%2
0
b) Right to Left : The expression evaluation starts from right to left direction
Example : X = 8 + 5 % 2
X=8+1
X=9
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6. Priority of Operators and their clubbing
• Each and every operator in C having its
priority and precedence fixed on the basis of
these property expression is solved.
• Operators from the same group may have
different precedence and associativity.
• If arithmetic expression contains more
operators, the execution will be performed
according to their priorities.
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7. Priority of Operators and their clubbing
• When two operators of the same priority are
found in the expression, the precedence is
given from the left most operators.
x=5*4+8/2 (8 / ( 2 * ( 2 * 2 ) ) )
2 1
1
2
3
3
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8. Comma and Conditional Operator
• It is used to separate two void main()
or more expressions. {
• It has lowest precedence
clrscr();
among all the operators
• It is not essential to printf(“%d %d”, 2+3, 3-2);
enclose the expressions }
with comma operators
within the parenthesis.
OUTPUT :
• Following statements are
valid 5 1
 a = 2, b = 4, c = a + b;
 ( a=2, b = 4, c = a + b );
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9. Conditional Operator (?:)
• This operator contains condition followed by
two statements and values.
• It is also called as ternary operator.
• Syntax :
Condition ? (expression1) : (expression2);
• If the condition is true, than expression1 is
executed, otherwise expression2 is executed
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10. Conditional Operator (?:)
• Example :
void main()
{
clrscr();
printf(“Maximum : %d”, 5>3 ? 5 : 3)
}
OUTPUT :
Maximum : 5
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11. Conditional Operator (?:)
• Example :
void main()
{
clrscr();
printf(“Maximum : %d”, 5>3 ? 5 : 3)
}
OUTPUT :
Maximum : 5
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12. Conditional Operator (?:)
• Example :
void main()
{
clrscr();
5 > 3 ? printf(“True”) : printf(“False”);
printf(“%d is ”, 5>3 ? : 3)
}
OUTPUT :
Maximum : 5
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13. Arithmetic Operator
• Two types of arithmetic operators
– Binary Operator
– Unary Operator
Operators
Unary Binary Ternary
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14. Arithmetic Operator
• Binary Operator
– An operator which requires two operator is know
as binary operator
– List of Binary Operators
Arithmetic Operator Operator Explanation Examples
+ Addition 2+2=4
- Subtraction 5–3=2
* Multiplication 2 * 5 = 10
/ Division 10 / 2 = 5
% Modular Division 11 % 3 = 2 (Remainder 2)
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15. Arithmetic Operator
• Unary Operator
– The operator which requires only one operand is
called unary operator
– List of unary operator are
Operator Description or Action
- Minus
++ Increment
-- Decrement
& Address Operator
Sizeof Gives the size of the operator
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16. Unary Operator - Minus
• Unary minus is used for indicating or changing
the algebraic sign of a value
• Example
int x = -50;
int y = -x;
• There is no unary plus (+) in C. Even though a
value assigned with plus sign is valid.
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17. Increment (++) and Decrement (--)
Operator
• The ++ operator adds value one to its
operand.
• X = X + 1 can be written as X++;
• There are two types ++ increment operator
base on the position are used with the
operand.
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18. Pre-increment (i.e. ++x)
int x =5, y;
y = ++x;
printf(“x = %dn y = %d”, ++x, y);
OUTPUT : x = x + 1;
x=7 y = ++x;
y=6 y = x;
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19. Post-increment (i.e. ++x)
int x =5, y;
y = x++;
printf(“x = %dn y = %d”, x++, y);
OUTPUT : y = x;
x=7 y = x++;
y=6 x = x + 1;
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20. Pre-decrement (i.e. --x)
int x =5, y;
y = --x;
printf(“x = %dn y = %d”, --x, y);
OUTPUT : x = x - 1;
x=3 y = --x;
y=4 y = x;
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21. Post-decrement (i.e. ++x)
int x =5, y;
y = x--;
printf(“x = %dn y = %d”, x--, y);
OUTPUT : y = x;
x=7 y = x--;
y=6 x = x - 1;
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22. sizeof operator
• The sizeof operator void main()
gives the bytes {
occupied by a variable. int x = 12;
• i.e. the size in terms of float y = 2;
bytes required in printf(“size of x : %d”, sizeof(x));
printf(“nsize of y :%d”, sizeof(y));
memory to store the
value. }
• The number of bytes OUTPUT :
occupied varies from sizeof x : 2
variable to variable sizeof y : 4
depending upon its
data type.
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23. ‘&’ Operator
• The ‘&’ returns the address of the variable in a
memory.
Address
int x = 15
2040
printf(“%d”,x);
Value
15
Variable X
printf(“n%u”,&x);
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24. Relational Operator
• These operators are used to distinguish
two values depending on their relations.
• These operators provide the relationship
between two expressions.
• If the relation is true it returns a value 1
otherwise 0 for false.
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25. Relational Operator
Operator Description or Action Example Return Value
> Greater than 5>4 1
< Less than 10 < 9 0
<= Less than or equal to 10 <= 10 1
>= Greater than or equal to 11 >= 5 1
== Equal to 2 == 3 0
!= Not Equal to 3 != 3 0
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26. Assignment Operator
• Assigning a value to a variable is very sample.
int x = 5
Assignment Operator
= *= /= %=
+= -= <<= >>=
>>>= &= ^= !=
int x = 10;
printf(“x = %dn”,x += 5); // x = x + 5; O/P x = 15
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27. Logical Operators
• The logical operator between the two
expressions is tested with logical operators.
• Using these operators, two expressions can be
joined.
• After checking the conditions, it provides
logical true(1) or false(0) status.
• The operands could be constants, variables
and expressions.
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28. Logical Operators
Operator Description or Action Example Return Value
&& Logical AND 5 > 3 && 5 < 10 1
|| Logical OR 8 > 5 || 8 < 2 1
! Logical NOT 8 != 8 0
i. The logical AND (&&) operator provides true result
when both expressions are true otherwise 0.
ii. The logical OR (||) operator true result when one of
the expressions is true otherwise 0.
iii. The logical NOT (!) provides 0 if the condition is true
otherwise 1.
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29. Bitwise Operator
• C supports a set of bitwise operators for bit
manipulation
Operators Meaning
>> Right Shift
<< Left Shift
^ Bitwise XOR (exclusive OR)
~ One’s Complement
& Bitwise AND
| Bitwise |
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30. void main() two bits means the inputted number is to be divided by 2 s where
Shifting of
{ s is the number of shifts i.e. in short y = n/2s
int x, y;
Where n = number and s = the number of position to be shift.
clrscr();
For example as Thethe program keyword (x) ;
print(“Read per Integer from
scanf(“%d”, &x); // input value for x = 8
Y = 8 / 22 = 2
2
x>>2;
y=x;
printf(“The Right shifted data is = %d”, y);
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}

31. void main() three bits left means the number is multiplied by 8; in short
Shifting of
{ y = n * 2s
where n = number
int x, y;
s = the number of position to be shifted
clrscr();
Asprint(“Read The Integer from keyword (x) ;
per the program
scanf(“%d”, &x); // input value for x = 2
Y=2*2 3
x<<=3;
y=x;
printf(“The Right shifted data is = %d”, y);
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}

32. void main()
{
int a, b, c;
clrscr();
printf(“Read the integers from keyboard ( a & b ) :”);
scanf(“%d %d”, &a, &b);
c = a & b;
printf(“The answer after ANDing is (C) = %d”, c);
}
OUTPUT :
Read the Integers from keyboard (a & b) : 8 4
The Answer after ANDing is (C) = 0
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33. Table of exclusive AND
X Y Outputs
0 0 0
0 1 0
1 0 0
1 1 1
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34. Binary equivalent of 8
Binary equivalent of 4
After execution
C=0
Binary equivalent of 0
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35. void main()
{
int a, b, c;
clrscr();
printf(“Read the integers from keyboard ( a & b ) :”);
scanf(“%d %d”, &a, &b);
c = a | b;
printf(“The answer after ORing is (C) = %d”, c);
}
OUTPUT :
Read the Integers from keyboard (a & b) : 8 4
The Answer after ORing is (C) = 12
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36. Table of exclusive OR
X Y Outputs
0 0 0
0 1 1
1 0 1
1 1 0
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37. Binary equivalent of 8
Binary equivalent of 4
After execution
C = 12
Binary equivalent of 0
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