Basic Operators

Overview

Operators perform operations on variables. Arithmetic (+, -, *, /, %) handles math, Assignment (=, +=) updates values, and Relational (==, !=, <, >) compares values.

Syntax

cpp

int a = 10, b = 3;

// Arithmetic
int sum = a + b; // 13
int mod = a % b; // 1 (Remainder)

// Assignment
a += 5; // a is now 15 (a = a + 5)

// Relational
bool isGreater = (a > b); // true
bool isEqual = (a == b);  // false

Common Pitfalls

Using a single `=` (assignment) instead of `==` (comparison) in an `if` statement condition.
Dividing two integers (e.g., `5 / 2`) results in integer division (`2`, not `2.5`).

Interview Tips

Understand the difference between prefix (++i) and postfix (i++). Prefix increments then returns the value; postfix returns the original value then increments. Prefix is generally slightly faster for complex iterators.

Real-World Example

Calculating if a number is even or odd using the modulo operator.

example

cpp

#include <iostream>
using namespace std;

int main() {
    int num = 42;
    if (num % 2 == 0) {
        cout << num << " is Even.\n";
    } else {
        cout << num << " is Odd.\n";
    }
    return 0;
}

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