Arithmetic operators in C++

Introduction

Arithmetic operators help you do math with numbers in your program. They let you add, subtract, multiply, divide, and find remainders easily.

Calculating the total price of items in a shopping cart.

Finding the average score of a student.

Counting how many days are left until an event.

Splitting a bill evenly among friends.

Converting units, like inches to centimeters.

Syntax

C++

result = a + b;  // addition
result = a - b;  // subtraction
result = a * b;  // multiplication
result = a / b;  // division
result = a % b;  // remainder (modulus) - only for integers

Use % only with whole numbers (integers) to get the remainder.

Division with integers gives an integer result (no decimals).

Examples

Adds 5 and 3 to get 8.

C++

int sum = 5 + 3;  // sum is 8

Subtracts 4 from 10 to get 6.

C++

int diff = 10 - 4;  // diff is 6

Multiplies 7 by 2 to get 14.

C++

int product = 7 * 2;  // product is 14

Divides 20 by 4 to get 5, and finds remainder of 20 divided by 3, which is 2.

C++

int quotient = 20 / 4;  // quotient is 5
int remainder = 20 % 3;  // remainder is 2

Sample Program

This program shows how to use all the basic arithmetic operators with two numbers, 15 and 4.

C++

#include <iostream>
using namespace std;

int main() {
    int a = 15;
    int b = 4;

    cout << "a + b = " << a + b << "\n";
    cout << "a - b = " << a - b << "\n";
    cout << "a * b = " << a * b << "\n";
    cout << "a / b = " << a / b << "\n";
    cout << "a % b = " << a % b << "\n";

    return 0;
}

Important Notes

Remember that dividing two integers gives an integer result, cutting off any decimal part.

Use floating-point numbers (like float or double) if you want decimals.

The modulus operator % only works with integers, not decimals.

Summary

Arithmetic operators let you do basic math in your code.

Use +, -, *, /, and % for addition, subtraction, multiplication, division, and remainder.

Division with integers drops decimals; use floating-point types for decimal results.