C# Arithmetic Operators - Complete Guide

Introduction to Arithmetic Operators

Arithmetic operators in C# are used to perform mathematical operations on numeric values. These operators support addition, subtraction, multiplication, division, and other operations needed for calculations.

C# arithmetic operators work with numeric types such as integers, floating-point numbers, and decimals. A strong understanding of these operators is essential for implementing calculations in your programs.

Basic Arithmetic Operators

The following example demonstrates addition, subtraction, multiplication, division, modulus, and the difference between integer and floating-point division:

Example

using System;

namespace ArithmeticOperatorsExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int a = 20;
            int b = 10;
            
            int sum = a + b;
            Console.WriteLine($"Addition: {a} + {b} = {sum}");
            
            int difference = a - b;
            Console.WriteLine($"Subtraction: {a} - {b} = {difference}");
            
            int product = a * b;
            Console.WriteLine($"Multiplication: {a} * {b} = {product}");
            
            int quotient = a / b;
            Console.WriteLine($"Division: {a} / {b} = {quotient}");
            
            int remainder = a % b;
            Console.WriteLine($"Modulus: {a} % {b} = {remainder}");
            
            double x = 20.0;
            double y = 3.0;
            double floatingQuotient = x / y;
            Console.WriteLine($"Floating-point division: {x} / {y} = {floatingQuotient}");
            
            int intResult = 7 / 2;          // integer division
            double doubleResult = 7.0 / 2;  // floating-point division
            Console.WriteLine($"Integer division 7/2 = {intResult}");
            Console.WriteLine($"Floating-point division 7.0/2 = {doubleResult}");
        }
    }
}

Output

Addition: 20 + 10 = 30
Subtraction: 20 - 10 = 10
Multiplication: 20 * 10 = 200
Division: 20 / 10 = 2
Modulus: 20 % 10 = 0
Floating-point division: 20 / 3 = 6.666666666666667
Integer division 7/2 = 3
Floating-point division 7.0/2 = 3.5

Increment and Decrement Operators

The increment operator (++) increases a variable’s value by 1, while the decrement operator (--) decreases it by 1. They can be used in prefix or postfix form:

Example

using System;

namespace IncrementDecrementExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int x = 5;
            
            Console.WriteLine($"Original x: {x}");
            Console.WriteLine($"x++: {x++}");
            Console.WriteLine($"After x++: {x}");
            
            Console.WriteLine($"++x: {++x}");
            Console.WriteLine($"After ++x: {x}");
            
            Console.WriteLine($"x--: {x--}");
            Console.WriteLine($"After x--: {x}");
            
            Console.WriteLine($"--x: {--x}");
            Console.WriteLine($"After --x: {x}");
            
            int counter = 0;
            Console.WriteLine($"\nCounter: {counter}");
            
            for (int i = 0; i < 5; i++)
            {
                Console.WriteLine($"Loop {i + 1}: counter = {counter++}");
            }
            
            Console.WriteLine($"Final counter: {counter}");
        }
    }
}

Output

Original x: 5
x++: 5
After x++: 6
++x: 7
After ++x: 7
x--: 7
After x--: 6
--x: 5
After --x: 5

Counter: 0
Loop 1: counter = 0
Loop 2: counter = 1
Loop 3: counter = 2
Loop 4: counter = 3
Loop 5: counter = 4
Final counter: 5

Operator Precedence and Associativity

Arithmetic operators follow precedence and associativity rules that control evaluation order. Multiplication, division, and modulus have higher precedence than addition and subtraction. Parentheses can be used to change the evaluation order explicitly.

Example

using System;

namespace OperatorPrecedenceExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int result1 = 2 + 3 * 4;      // 14
            int result2 = (2 + 3) * 4;    // 20
            
            Console.WriteLine($"2 + 3 * 4 = {result1}");
            Console.WriteLine($"(2 + 3) * 4 = {result2}");
            
            double complexResult = 10 + 2 * 3 - 4 / 2 + 5 % 3;
            Console.WriteLine($"10 + 2 * 3 - 4 / 2 + 5 % 3 = {complexResult}");
            
            double controlledResult = (10 + 2) * (3 - 4) / 2 + 5 % 3;
            Console.WriteLine($"(10 + 2) * (3 - 4) / 2 + 5 % 3 = {controlledResult}");
            
            double preciseCalculation = (10.0 + 2.5) * 3.0 / 4.0;
            Console.WriteLine($"(10.0 + 2.5) * 3.0 / 4.0 = {preciseCalculation}");
            
            int trickyResult = 3 / 2 * 4;  // 4 due to integer division
            Console.WriteLine($"3 / 2 * 4 = {trickyResult}");
            
            double correctResult = 3.0 / 2 * 4;  // 6.0
            Console.WriteLine($"3.0 / 2 * 4 = {correctResult}");
        }
    }
}

Output

2 + 3 * 4 = 14
(2 + 3) * 4 = 20
10 + 2 * 3 - 4 / 2 + 5 % 3 = 16
(10 + 2) * (3 - 4) / 2 + 5 % 3 = -4
(10.0 + 2.5) * 3.0 / 4.0 = 9.375
3 / 2 * 4 = 4
3.0 / 2 * 4 = 6

C# Arithmetic Operators - Complete Guide

Introduction to Arithmetic Operators

Basic Arithmetic Operators

The following example demonstrates addition, subtraction, multiplication, division, modulus, and the difference between integer and floating-point division:

Example

using System;

namespace ArithmeticOperatorsExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int a = 20;
            int b = 10;
            
            int sum = a + b;
            Console.WriteLine($"Addition: {a} + {b} = {sum}");
            
            int difference = a - b;
            Console.WriteLine($"Subtraction: {a} - {b} = {difference}");
            
            int product = a * b;
            Console.WriteLine($"Multiplication: {a} * {b} = {product}");
            
            int quotient = a / b;
            Console.WriteLine($"Division: {a} / {b} = {quotient}");
            
            int remainder = a % b;
            Console.WriteLine($"Modulus: {a} % {b} = {remainder}");
            
            double x = 20.0;
            double y = 3.0;
            double floatingQuotient = x / y;
            Console.WriteLine($"Floating-point division: {x} / {y} = {floatingQuotient}");
            
            int intResult = 7 / 2;          // integer division
            double doubleResult = 7.0 / 2;  // floating-point division
            Console.WriteLine($"Integer division 7/2 = {intResult}");
            Console.WriteLine($"Floating-point division 7.0/2 = {doubleResult}");
        }
    }
}

Output

Addition: 20 + 10 = 30
Subtraction: 20 - 10 = 10
Multiplication: 20 * 10 = 200
Division: 20 / 10 = 2
Modulus: 20 % 10 = 0
Floating-point division: 20 / 3 = 6.666666666666667
Integer division 7/2 = 3
Floating-point division 7.0/2 = 3.5

Increment and Decrement Operators

The increment operator (++) increases a variable’s value by 1, while the decrement operator (--) decreases it by 1. They can be used in prefix or postfix form:

Example

using System;

namespace IncrementDecrementExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int x = 5;
            
            Console.WriteLine($"Original x: {x}");
            Console.WriteLine($"x++: {x++}");
            Console.WriteLine($"After x++: {x}");
            
            Console.WriteLine($"++x: {++x}");
            Console.WriteLine($"After ++x: {x}");
            
            Console.WriteLine($"x--: {x--}");
            Console.WriteLine($"After x--: {x}");
            
            Console.WriteLine($"--x: {--x}");
            Console.WriteLine($"After --x: {x}");
            
            int counter = 0;
            Console.WriteLine($"\nCounter: {counter}");
            
            for (int i = 0; i < 5; i++)
            {
                Console.WriteLine($"Loop {i + 1}: counter = {counter++}");
            }
            
            Console.WriteLine($"Final counter: {counter}");
        }
    }
}

Output

Original x: 5
x++: 5
After x++: 6
++x: 7
After ++x: 7
x--: 7
After x--: 6
--x: 5
After --x: 5

Counter: 0
Loop 1: counter = 0
Loop 2: counter = 1
Loop 3: counter = 2
Loop 4: counter = 3
Loop 5: counter = 4
Final counter: 5

Operator Precedence and Associativity

Example

using System;

namespace OperatorPrecedenceExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int result1 = 2 + 3 * 4;      // 14
            int result2 = (2 + 3) * 4;    // 20
            
            Console.WriteLine($"2 + 3 * 4 = {result1}");
            Console.WriteLine($"(2 + 3) * 4 = {result2}");
            
            double complexResult = 10 + 2 * 3 - 4 / 2 + 5 % 3;
            Console.WriteLine($"10 + 2 * 3 - 4 / 2 + 5 % 3 = {complexResult}");
            
            double controlledResult = (10 + 2) * (3 - 4) / 2 + 5 % 3;
            Console.WriteLine($"(10 + 2) * (3 - 4) / 2 + 5 % 3 = {controlledResult}");
            
            double preciseCalculation = (10.0 + 2.5) * 3.0 / 4.0;
            Console.WriteLine($"(10.0 + 2.5) * 3.0 / 4.0 = {preciseCalculation}");
            
            int trickyResult = 3 / 2 * 4;  // 4 due to integer division
            Console.WriteLine($"3 / 2 * 4 = {trickyResult}");
            
            double correctResult = 3.0 / 2 * 4;  // 6.0
            Console.WriteLine($"3.0 / 2 * 4 = {correctResult}");
        }
    }
}

Output

2 + 3 * 4 = 14
(2 + 3) * 4 = 20
10 + 2 * 3 - 4 / 2 + 5 % 3 = 16
(10 + 2) * (3 - 4) / 2 + 5 % 3 = -4
(10.0 + 2.5) * 3.0 / 4.0 = 9.375
3 / 2 * 4 = 4
3.0 / 2 * 4 = 6

C# Basics

C# OOP

C# Quizzes

C# Arithmetic Operators - Complete Guide

Introduction to Arithmetic Operators

Basic Arithmetic Operators

Increment and Decrement Operators

Operator Precedence and Associativity

C# Arithmetic Operators - Complete Guide

Introduction to Arithmetic Operators

Basic Arithmetic Operators

Increment and Decrement Operators

Operator Precedence and Associativity