For Students.

1. C Language
Operators
Engr. Qazi Shahzad Ali

2. C Language Operators
 Arithmetic Operators
 Increment Operator
 Decrement Operator
 Relational Operator
 Logical Operator
 Equality Operator
 Assignment Operator
 Conditional Operator
 Arithmetic expression
2

3. 1-Arithmetic Operators
Operator Symbol Example
Multiplicatio
n
* a*b
Division / a/b
Addition + a+b
Subtraction - a-b
Modulus % a%b
3

4. Example for integers:
Exampl
e
Result
a*b 30
a/b 3
a+b 13
a-b 7
a%b 1
a=10
b=3
4

5. Example for floating point variable:
Exampl
e
Result
a*b 25.0
a/b 6.25
a+b 14.5
a-b 10.5
a%b NA
a=12.5
b=2.0
5

6. Example for Character:
Example Result
C1 80
c1+c2 164
c1+c2+5 169
c1+c2+
‘5’
217
Char C1,
C2
C1=‘T’
C2=‘P’
The ASCII code of ‘5’ is 53
6

7. 2-Increment & Decrement Operators:
Operator Symbol Example
Increment ++ a++ or ++a
Decrement -- a-- or --a
7

8. 2-Increment & Decrement Operators:
Operator Symbol Example
Increment ++ a++ or ++a
Decrement -- a-- or --a
8

9. 3-Relational Operators
(use in decision making)
Operator
Symbo
l
Example
less than < a<b
greater than > a>b
less than or equal <= a<=b
greater than or
equal
>= a>=b
equal == a==b
Not equal != a!=b9

10. Example: i=1, j=2, k=3
Expression Meaning Value
i<j Correct 1
(i+j)>=k Correct 1
(j+k) > (i+5) wrong 0
K!=3 wrong 0
J==2 Correct 1
10

11. 4-Logical Operator
Operator Symbol Example
AND && a<b && c>b
OR || a<b || c>b
NOT ! !(a<b)
11

12. Example: integer=i=7, float=f=5.5, character=c=‘w’
Expression Meaning Value
(i>=6)&&(c==‘w’) Correct 1
(i>6)||(c==119) Correct 1
(f<11)&&(i>100) wrong 0
(c!=‘p’)||(i+f)<=10 Correct 1
12

13. Operant Result
x y !x !y x&&y x||y
0 0 1 1 0 0
0
Non-
zero
1 0 0 1
Non-
zero
0 0 1 0 1
Non-
zero
Non-
zero
0 0 1 1
Logical Operators: AND, OR, NOT
13

14. Example: i=7, f=5.5
Expression Alternative expression Meanings
f>5 correct 1
!(f>5) wrong 0
i<=3 wrong 0
!(i<=3) correct 1
i>(f+1) correct 1
!(i>(f+1)) wrong 0
14

15. Bitwise Operator
Operator Symbol Example
AND & a&b
OR | (Pipe) a|b
Exclusive OR ^ (Caret) a^b
Complement ~ (Tilde) ~a
Right Shift >> a>>b
Left Shift << a<<b
15

16. Address and Indirection Operator:
Operator Symbol Example
Address & addr=&var
Indirection * Value=*addr
16

17. Memory Location:
3
i
6552
4
Location Name
Value at Location
Location Number
17

18. Conditional Operator
Generic Expression Example
result=(expression) ? Value1: value 2; max=(a>b) ? a:b;
If the expression is true (other than 0) then value 1 will be assigned to variable
“result”
If the expression is false (equal to 0) then value 2 will be assigned to variable “result”
18

19. Sizeof Operator:
Generic
Expression
Example
sizeof ()
sizeof(int), sizeof (struct
emp)
19

20. Algebraic Expression:
Algebraic Expression C Expression
a x b- c x d A *b-c*d
(m+n)(a+b) (m+n)*(a+b)
3x2+2x+5 3*x*x+2*x+5
a+b+c/d+e (a+b+c)/(d+e)
[2by/d+1-x/3(z+y)] 2*b*y/(d+1)-x/3*(z+y)
20

21. Assignment Operators
Operator Symbol Example
Equal(assign the value, different from
==)
= a=b
addition += a+=b (same as a=a+b)
subtraction -= a-=b (same as a=a-b)
multiplication *= a*=b (same as a=a*b)
division /= a/+b (same as a=a/b)
remainder %= a%=b (same as a=a%b)
Bitwise AND &= a&=b (same as a=a&b)
Bitwise inclusive OR |= a|=b (same as a=a|b)
Bitwise exclusive OR ^= a^=b (same as a=a^b)
Left shift <<= a<<=2 (same as a=<<2)
Right shift >>= a>>=3 (same as a=>>3)
21

22. Example: Assignment Operator
Expression Alternative expression
Variable 1+= variable 2 Variable 1=variable1 +variable 2
Variable 1-= variable 2 Variable 1=variable1 -variable 2
Meanings: The variable 1 on left side will add value
of variable 2 on right side and the resultant new value
will be assign to variable 1
22

23. Integer and Float Conversions:
24

24. Escape Sequence:
Escape sequence is used in the printf() function to do something to
the output.
Escape
Sequence
Effect
a Beep sound, alarm
b Backspace
f Form feed (for printing)
n New line
r Carriage return (move the curser to beginning of current line)
t Tab
v Vertical tab
Backslash (to print at output)
” Used to print (“) sign
’ Used to print (‘) sign
27

25. Format Specifier
Tells the printf() function the format of the output to be printed put
No Format Specifier Output Type Output Example
1 %d or %i Signed decimal integer (short) 76
2 %u Unsigned decimal integer (short) 76
3 %o Unsigned octal integer 134
4 %x Unsigned hexadecimal (small letter) 9c
5 %X Unsigned hexadecimal (capital letter) 9C
6 %f Integer including decimal point 76.0000
7 %e Signed floating point (using e notation) 7.6000e+01
8 %E Signed floating point (using E notation) 7.6000E+01
9 %g The shorter between %f and %e 76
10 %G The shorter between %f and %E 76
11 %c Single Character (both for signed & unsigned) ‘7’
12 %s String “76”
28

26. Filed–Width Specifiers:
With the help of this
Interpretation of a variable’s type
Width of the field
Number of decimal places printed
Justification
29

27. Example # 1: Field-Width Specifer:
A g e i s 3 3 .
A g e i s 3 3 .
A g e i s 3 3 .
printf(“Age is %2d.”, age);
printf(“Age is %4d.”, age);
printf(“Age is %6d.”, age);
30

28. Example # 2: Field-Width Specifer:
main()
{
Float temp=27.25;
printf(“The temperature is %f.”, temp);
}
Output:
The Temperature is 27.250000
main()
{
Float temp=27.25;
printf(“The temperature is %.2f.”, temp);
}
Output:
The Temperature is 27.25
31

29. Study the following example:
main()
{
printf(“%.1f%8.1f%8.1fn”,3.0,12.5,523.3);
printf(“%.1f%8.1f%8.1fn”,300.0,1200.5,52300.3);
}
What will be the output??
32

30. Output of Previous Example:
 output
3.0 12.5 523.3
300.0 1200.5 52300.3
In other way
3 . 0 1 2 . 5 5 2 3 . 3
3 0 0 . 0 1 2 0 0 . 5 5 2 3 0 0 . 3
8 8
8 8
33

31. Study the following example:
main()
{
printf(“%-.1f%-8.1f%-8.1fn”,3.0,12.5,523.3);
printf(“%-.1f%-8.1f%-8.1fn”,300.0,1200.5,52300.3);
}
What will be the output??
34

32. Output of Previous Example:
 output
In other way
3 . 0 1 2 . 5 5 2 3 . 3
3 0 0 . 0 1 2 0 0 . 5 5 2 3 0 0 . 3
8 8
8 8
300.0 1200.5 52300.3
3.0 12.5 523.3
35

33. Explanation:
%8.1f
%
8 . 1
f
Signals format
specification
field width
# of digits to the
right of decimal
Indicates
decimal-format
floating point
36

34. Scanf and Assignment:
scanf:
It is used to save the function input into its relavent
variable.
Assignment operator:
Its takes answer of a statement and saves into other
variable
37

35. Hierarchy of Operation:
Priority operator Description
1st * / %
multiplication, division ,
modular division
2nd + - addition , subtraction
3rd = Assignment
38

36. Associativity of operators
 When two expression contains two operators of
equal priority the tie between them is settled using
the associativity of the operators .
1. Left to right (left operand must be unambiguous)
2. Right to left (right operand must be unambiguous)
Means it must not be involved in evaluation of any
other sub-expression
Example:
a=3/2*5
39

37. Example: a=3/2*5
Operator left right remark
/ 3 2 or 2*5
Left operand
is
unambiguous
, Right is not
* 3/2 or 2 5
Right
operand is
unambiguous
, Left is not
Meanings: Since both have / and * have L to R associativity and
Only / has unambiguous, left operand (necessary condition for L to R associativity
is performed earlier.
40

38. Operator Associativity Chart
44

39. Evaluation:
kk=3/2*4+3/8+3
Solution:
 kk=3/2*4+3/8+3
 kk=1*4+3/8+3 operation : /
 kk=4+3/8+3 operation : *
 kk=4+0+3 operation : /
 kk=4+3 operation : +
 kk=7 operation : +
45

40. 46
Solve the Question
i=2*3/4+4/4+8-2+5/8

41. Evaluation Exercise:
 i=2*3/4+4/4+8-2+5/8
Solution:
 i=2*3/4+4/4+8-2+5/8
 i=6/4+4/4+8-2+5/8 operation : *
 i=1+4/4+8-2+5/8 operation : /
 i=1+1+8-2+5/8 operation : /
 i=1+1+8-2+0 operation : /
 i=2+8-2+0 operation : +
 i=10-2+0 operation : +
 i=8+0 operation : -
 i=8 operation : +
47

42. 48