C operators

C programming language provides several operators to perform different kind to operations. There are operators for assignment, arithmetic functions, logical functions and many more. These operators generally work on many types of variables or constants, though some are restricted to work on certain types. Most operators are binary, meaning they take two operands. A few are unary and only take one operand.

Arithmetic Operators
Arithmetic operators include the familiar addition (+), subtraction (-), multiplication (*) and division (/) operations. In addition there is the modulus operator (%) which gives the remainder left over from a division operation.
Example Program

Relational Operators
Relational operators compare operands and return 1 for true or 0 for false. The following relational operators are available

Symbol Meaning
< Less than
> Greater than
<= Less than or equal to
>= Greater than or equal to
== Equal to
!= Not equal to

Example

int a=35,b=90,c;

c=a < b;

The value of c after execution of above code is 1 since the condition 35 < 90 is true

C Logical Operators
The logical operators are || for a logical or and && for a logical and and ! for logical not. The and and or operate on two boolean values of true or false. In C, an expression that evaluates to 0 is false and an expression that evaluates to non-zero is true. These operators return 1 for true or 0 for false.

The following table shows the results of applying these operators to different boolean values

Left Operation Right Result

True && True True
False && True False
True && False False
False && False False
True || True True
False || True True
True || False True
False || False False

As you can see from the table, an and operation is true only when both its operands are true. An or operation is true if either one of its operands is true.

The table also shows that these operators can do what is called “lazy evaluation” or “short circuit evaluation”. The operands are evaluated from left to right. For an and operation, if the left operand is false, the right operand is not even evaluated because the result is known to be false. For an or operation, if the left operand is true the right operand is not evaluated because the result will be true.

Example
int x=55,y=67,z=55,w;
w=(x==z)&&(x>y);

The value of w from the above code is 0 since 55==55 is true but 55>67 is false
true && false = false.

Assignment Operators

C has several assignment operators available - one simple assignment operator and several convenience assignment operators that combine arithmetic or bitwise operations with assignment. The operators are as follows:

Symbol Meaning
= Assignment
*= Multiply and assign
/= Divide and assign
%= Modulo and assign
+= Add and assign
-= Subtract and assign

Example #1
int a,b=33;
a=b;

Example #2
int a=100,b=50;
a+=b;

In the second example a+=b means a=a+b which is evaluated as
a=100+50 which is 150.

Conditional operator (or) Ternary Operator

The conditional operator is unusual in that it takes three operands. The syntax of this operator is like this:

Condition ? Expression1 : Expression2;

You can think of the conditional operator as if it were a function that works like this:

if ( Condition )

return Expression1;
else
return Expression2;

The Condition expression must evaluate to true or false. If it is true Expression1 is evaluated and its value is returned. If Condition is false Expression2 is evaluated and its value is returned. Both Expression1 and Expression2 must be the same type (or convertible to the same type).

Example
int a=101,b=50,c;
c=a>b?10:20;

In the above code the value of c will be 10 as the condition 101>50 is true.