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Operators in C

Nihar Ranjan Roy

Arithmetic Operators

Operator name Syntax

Basic assignment a = bAddition a + b

Subtraction a - b

Unary plus (integer promotion) +a

Unary minus (additive inverse) -a

Multiplication a * b

Division a / b

Modulo (remainder) a % b

IncrementPrefix ++aSuffix a++

DecrementPrefix --aSuffix a--

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int i=5;

printf("%d",++i);

printf("%d",i++);

printf("%d",i);

6 6 7

Comparison operators/Relational operators

Operator name Syntax

Equal to a == b

Not equal to a != b

Greater than a > b

Less than a < b

Greater than or equal to a >= b

Less than or equal to a

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Bitwise operators

Operator name Syntax

Bitwise NOT ~a

Bitwise AND a & b

Bitwise OR a | b

Bitwise XOR a ^ b

Bitwise left shift a > b

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a=72, b=184C=a&b;

72 0 1 0 0 1 0 0 0

184 1 0 1 1 1 0 0 0

8 0 0 0 0 1 0 0 0

int i=16;i=ib)?a:b; //biggest of a & bprintf("%d",c);

Operator Precedence

The precedence determines the order of binding in chainedexpressions, when it is not expressly specified by parentheses.

For example,

++x*3 It is ambiguous without some precedence rule(s). The precedence table tells us that:

x is 'bound' more tightly to ++ than to *,

so that whatever ++ does (now or latersee below), it does it ONLYto x (and not to x*3);

it is equivalent to (++x, x*3).

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Operator Precedence

Precedence Operator Description Associativity

1

++ Suffix increment

Left-to-right

-- Suffix decrement

() Function call

[] Array subscripting

. Element selection by reference

-> Element selection through pointer

2

++ Prefix increment

Right-to-left

-- Prefix decrement+ Unary plus- Unary minus

!Logical NOT

~ Logical bitwise NOT(type) Type cast

& Address-of

sizeof Size-of

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Operator Precedence..

3

* Multiplication

Left-to-right

/ division% modulus (remainder)

4+ Addition

- subtraction

5

> Bitwise right shift

6

< For relational operators < respectively For relational operators > respectively>= For relational operators respectively

7== For relational = respectively!=

8 & Bitwise AND

9 ^ Bitwise XOR (exclusive or)

10 | Bitwise OR (inclusive or)

11 && Logical AND

12 || Logical OR

Precedence Operator Description Associativity

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Operator Precedence..

15 ?: Ternary conditional

Right-to-left13

= Direct assignment

+= Assignment by sum

-= Assignment by difference

*= Assignment by product

/= Assignment by quotient

%= Assignment by remainder

= Assignment by bitwise right shift

&= Assignment by bitwise AND^= Assignment by bitwise XOR

|= Assignment by bitwise OR15 , Comma Left-to-right

Precedence Operator Description Associativity

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Evaluate

Evaluate 3*x++,

where though the post-fix ++ is designed to act AFTER the entire expression isevaluated, the precedence table makes it clear that ONLY x gets incremented(and NOT3*x);

it is functionally equivalent to something like (tmp=3*x, ++x, tmp) with tmp beinga temporary value.

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Casting (Implicit & Explicit)

Implicit Casting (automatic transformation) works in a way that a variable (operand)of data type that is smaller in length (than data type of second variable) (operand),transforming internally to variable of data type with longer number length.

Shortint

intUnsigned

intLong int

Unsignedlong int

float doubleLongdouble

float a;

int b=1,c=2;

a=b+c;

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Casting (Implicit & Explicit)

Explicit Casting

When one data types has higher priority then automatic transformation

This is not done automatically, the programmer has to do it explicitly

Syntax

(data_type) operand

Float a;

int b=1,c=2;

a=b/c;

a=(float) b/c;

//output is 0.00

//output is 0.5000

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Overflow

char a=255;

a=a+1

printf("%d",a);

Output?

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0