Operators In C

Operators in C

C has a rich set of operators (i.e., things like + – * / ), which allow you to write complicated expressions quite compactly. General expressions are formed by joining together constants and variables (operands) via various operators.

Operators in C fall into a number of classes:

Arithmetic operators, Unary operators, Relational and Logical operators, Assignment operators, Equality operators, and the Conditional operator.\

Unary Operators

Unary operators are operators that only take one argument.

+123  positive 123
-123  negative 123
!i    logical negation (i.e., 1 if i is  zero, 0 otherwise)
++i   adds one to i, and returns the new value of i
––i   subtracts one from i, and returns the new value of i
i++   adds one to i, and returns the old value of i
i––  subtracts one from i, and returns the old value of i 

++i or i++ are also called increment or decrement operators. It only ads 1 to the value.

Example 1: Using

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
	int val=100;
	printf("Val is %d",val);  // val is 100
	val++; 						//val is 101
	printf("\nVal is %d",val);
	++val;                      //val is 102
	printf("\nVal is %d",val);
	val--;						//val is 101
	printf("\nVal is %d",val);
	
	printf("\nVal is %d",++val);//here val is 102
	printf("\nVal is %d",val++);//here val 102. prints 101 but increments is done after print
	
	//if you print here val will be 103
	
	return 0;
}

Binary Operators

Binary operators work on two operands (‘binary‘ here means 2 operands, not in the sense of base-2 arithmetic).

+   addition
–   subtraction
*   multiplication
/   division
%   remainder (e.g., 2%3 is 2), also called  'modulo'
<<  left-shift (e.g., i<<j is i shifted to the left by j bits)
>>  right-shift
&   bit wise AND
|   bit wise OR
^   bit wise exclusive-OR 
&&  logical AND (returns 1 if both operands are non-zero; else 0)
||  logical OR (returns 1 if either operand is  non-  zero; else 0)
<   less than (e.g., i<j returns 1 if i is less than j)
>   greater than
<=  less than or equal
>=  greater than or equal ==   equals
!=  does not equal
?   conditional operator 

Example 2:

#include <stdio.h>
#include <stdlib.h>



int main(int argc, char *argv[]) {
	int a=10;
	int b=20;
	int c=a+b;
	printf("The sum is %d",c);
	return 0;
}

Assignment Operators

The most common assignment operator in C is the equals operator, =. It is used to change the value of a variable. For instance, the expression:  f = 3.4; causes the floating-point value 3.4 to be assigned to the variable f.

Multiple assignments are permissible in C. For example,

i = j = k = 4;

causes the integer value 4 to be assigned to i, j, and k, simultaneously.

Arithmetic Assignment Operators in C

=   assignment
+=  addition assignment
-=  subtraction assignment
*=  multiplication assignment
/=  division assignment
%=  remainder/modulus assignment
&=  bit wise AND assignment
|=  bit wise OR assignment
^=  bit wise exclusive OR assignment
<<= left shift assignment
>>= right shift assignment 

Example 3:

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
	int price=100;
	int quantity=2;
	price*=quantity;   // it is equal to price=price*quantity
	printf("Total amount is %d",price);
	return 0;
}

Arithmetic Operators

There are four main arithmetic operators in C:

   addition         +
   subtraction      –
   multiplication   *
   division         /  

There is no built-in exponentiation operator in C . Instead, there is a library function (pow) which carries out this operation.

e.g. x2 is represented as x * x

Operation	C Operator	Algebraic Expression	C Expression
Addition	+	f + 7	f + 7
Subtraction	–	a – b	a – b
Multiplication	*	bm	b * m
Division	/	x / y or x ÷ y	x / y
Modulus	%	r mod s	r % s

Relational Operators

Relational operators are used to compare two or more operators. The result of comparison is either true or false.

Symbol	Operator	Example
<	Less Than	a < b
>	Greater Than	a > b
= =	Equal to	a  =  b
<=	Less or Equal	a <= b
>=	Greater or Equal	a >=b
<>	Not Equal	a <> b

Example 4:

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
	int cost=250;
	int price=300;
	printf("Answer is : %d",cost<price);
	printf("\n");
	printf("Answer is : %d",cost==price);
}

Output:

Answer is : 1
Answer is : 0

Logical Operators

Effects  on relational expression’s results also AND, OR combines two or more Relational expressions,  Results will be returned either TRUE( 1 ) or FALSE ( 0 ) regards with specific situations.

Symbol	Operator	Example
AND	AND	A< b AND c > d
OR	OR	a <  b OR c > d
NOT	NOT	NOT ( a < b )

Suppose we have the following values:

a =  2, b = 5, c = 9, d = 7

Symbol	Operator	Example
AND	a< b AND c > d	1
OR	a <  b OR c > d	1
NOT	NOT ( a < b )	0

Code Example