C Arithmetic Operators

In C programming, arithmetic operators perform mathematical operations on numeric values, such as integers and floating-point numbers. Here are the most common arithmetic operators in C.

Operator	Description	Example
+	Addition (add two operands)	4 + 6 result is 10
-	Subtraction (subtract right operand from the left operand)	5 - 2 result is 3
*	Multiplication (multiply two operands)	2 * 4 result is 8
/	Division (divide left operand by right operand)	9 / 3 result is 3
%	Modulus (divide left operand by right operand and get remainder)	22 % 7 result is 1
Unary negation -	Unary operator. Returns the negation of its operand.	If x =3 then -x results as -3
++	Pre- or post-increment	If x is 5 then x++ will first return 5 and then increment in x to make it 6. If x is 5 then ++x will first increment x and set its value to 6 and then return its value i.e., 6.
--	Pre- or post-decrement	If x is 5 then x-- will first return 5 and then decrement in x to make it 4. If x is 5 then --x will first decrement x and set its value to 4 and then return its value i.e., 4.

The Addition Operator ( + ) in C

The addition operator ( + ) is used to add two operands.

You are already familiar with:

int x = 10;

You can also write,

int x = 5 + 5;

You can use variables as operands.

int x = 2;
int y = 3;
int z= x + y;

You can mix variables and numbers as operands.

int x = 2;
int y = x + 2;

You can also add float values.

float x = 2.5;
float y = 3.2;
float z= x + y;  // 5.7

The Subtraction Operator ( - ) in C

The subtraction operator subtract right operand from the left operand.

Example:

int x = 3;
int y = 2;
int z = x - y;  // 1

The Multiplication Operator ( * ) in C

The multiplication operator multiply two operands.

Example:

int x = 2;
int y = 3;
int z = x * y;  // 6

The Division Operator ( / ) in C

The division operator divides left operand by right operand. When / is used with int or char the decimal part of the remainder value is truncated.

Example:

int x = 3;
int y = 2;
printf("%d ", x/y);  // 1 instead of 1.5

If the right operand is zero, then the result is un-defined or floating point exception.

int x = 3;
int y = 0;
printf("%d ", x/y);  // Floating point exception

The Modulus Operator ( % ) in C

The modulus operator divides left operand by right operand and get remainder. The modulus operator does not support float and double.

int x = 11;
int y = 3;
printf("%d ", x%y);  // 2

If the right operand is zero, then the result is un-defined or floating point exception.

The Unary Negation Oprator ( - ) in C

The unary negation operator simply return negation of its operand.

Example:

int x = 2;
int y;
y = -x;
printf("%d ", y);  // -2

The Pre or Post-Increment Operator ( ++ ) in C

The increment operator adds 1 to its operand. It could be pre increment or post increment.

The pre-increment means. First increment then return the value.
The post increment means. First return the value then increment.

Example: Pre-Increment

int x = 3;
int y;
//First value of x will be incremented by 1. 
//The x will become 4, then value of x, 4 will be assigned to variable y 
y = ++x;
printf("%d %d", x, y);  // 4 4

Example: Post-Increment

int x = 3;
int y;

// First value of x, 3 will be assigned to y. Then x will be incremented by 1.
y = x++;
printf("%d %d", x, y);  // 4 3

The Pre or Post-Decrement Operator ( -- ) in C

The decrement operator subtract 1 from its operand. It could be pre decrement or post decrement.

The pre-decrement means. First decrement then return the value.
The post decrement means. First return the value then decrement.

Example: Pre-Decrement

int x = 5;
int y;

//First value of x will be decremented by 1. 
//The x will become 4, then value of x, 4 will be assigned to variable y.
y = --x;
printf("%d %d", x, y); // 4 4

Example: Post-Decrement

int x = 5;
int y;

//First value of x, 5 will be assigned to y. Then x will be decremented by 1.
y = x--;
printf("%d %d", x, y);  // 4 5