Operators

Operators are symbols that tell the compiler to perform specific mathematical or logical manipulations. In C++, we group them into three main categories that you’ll use constantly.

1. Arithmetic Operators

These are used for basic math.

OperatorName DescriptionExample (a=10,b=3)

+ AdditionAdds two operands a + b = 13

- SubtractionSubtracts second from first a - b = 7

* MultiplicationMultiplies two operands a * b = 30

/ DivisionDivides first by second a / b = 3 (Integer division)

% ModuloReturns the remainder a \% b = 1$

Note on Modulo (%): This is incredibly useful for checking if a number is even or odd (e.g., num % 2 == 0).

2. Relational (Comparison) Operators

Used to compare two values. They always return a Boolean (true or false).

• == (Equal to) — Don't confuse with = which assigns a value!

• != (Not equal to)

• > (Greater than) / < (Less than)

• >= (Greater than or equal to) / <= (Less than or equal to)

3. Logical Operators

Used to combine multiple conditions.

• && (AND): True only if both conditions are true.

• || (OR): True if at least one condition is true.

• ! (NOT): Reverses the result (True becomes False).

#include <iostream>
using namespace std;

int main() {
    double price = 100.0;
    int quantity = 3;
    double taxRate = 0.08; // 8% tax
    bool isMember = true;

    // 1. Arithmetic: Calculate subtotal
    double subtotal = price * quantity;
    
    // 2. Arithmetic: Calculate tax
    double totalTax = subtotal * taxRate;
    double finalPrice = subtotal + totalTax;

    // 3. Relational & Logical: Check for discount eligibility
    // Eligible if spending > 200 AND they are a member
    bool getsDiscount = (finalPrice > 200.0) && isMember;

    cout << "Subtotal: $" << subtotal << endl;
    cout << "Total with Tax: $" << finalPrice << endl;
    cout << "Discount Eligible: " << (getsDiscount ? "Yes" : "No") << endl;

    return 0;
}