Operators and Expressions in C++

Imagine you’re playing a video game.
Your character collects coins, loses health, gains power, and fights enemies. Behind the scenes, the game constantly calculates things like:

• health = health – damage
• score = score + coins
• levelUp = (score > 2000)
• isAlive = (health > 0 && lives > 0)

Games run because the computer uses operators and expressions to make decisions and update values.

Today, you’ll learn the same tools games, apps, and robots use to think, compare, and react.

By the end of this lesson, you will build a Mini Game Status Calculator that updates a player's score, health, and level status using operators.

Mini Game Status Calculator

You are designing a small game system.
Your program should:

1. Start with a score of 50
2. Add 30 points collected by the player
3. Reduce health by 10
4. Check if the player has leveled up (score >= 100)
5. Check if the player is alive (health > 0)

Your output should look like:

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==============================
   GAME STATUS
   Score: 80
   Health: 90
   Level Up: true
   Player Alive: true
==============================

This small project teaches how operators create logic inside real applications.

The Concept: Operators in C++

Operators are symbols that tell the computer what action to perform.

1. Arithmetic Operators

Used for calculations:

• + addition
• - subtraction
• * multiplication
• / division
• % remainder

Example:

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int score = 50 + 30;

2. Relational Operators

Used to compare values:

• == equal
• != not equal
• > greater
• < less
• >= greater or equal
• <= less or equal

Example:

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bool isAdult = (age >= 18);

3. Logical Operators

Used for decision-making:

• && AND
• || OR
• ! NOT

Example:

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bool canEnter = (age >= 18 && hasTicket == true);

4. Increment and Decrement

These update values faster:

• ++ increases by 1
• -- decreases by 1

Example:

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score++;   // same as score = score + 1
health--;  // same as health = health - 1

5. Assignment Operators

Used to store and update values:

• = sets a value
• += adds and assigns
• -= subtracts and assigns

Examples:

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score += 10;   // score = score + 10
health -= 5;   // health = health - 5

6. Operator Precedence

Just like math (BODMAS), C++ follows an order:

Multiplication and division happen before addition and subtraction.

Example:

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int result = 5 + 2 * 3; // result is 11, not 21

Because 2 * 3 happens first.

Let’s Build the Game Status Calculator

Here is the complete C++ program:

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#include <iostream>
using namespace std;

int main() {
    int score = 50;
    int health = 100;

    score += 30;     // add points
    health -= 10;    // reduce health

    bool levelUp = (score >= 100);
    bool playerAlive = (health > 0);

    cout << "==============================" << endl;
    cout << "   GAME STATUS" << endl;
    cout << "   Score: " << score << endl;
    cout << "   Health: " << health << endl;
    cout << "   Level Up: " << levelUp << endl;
    cout << "   Player Alive: " << playerAlive << endl;
    cout << "==============================" << endl;

    return 0;
}

Run and see it execute instantly.

Try asking the AI:

“Explain how assignment operators like += and -= work in C++ with examples.”

How It Works

• Arithmetic operators update your game values.
• Relational operators check conditions like leveling up.
• Logical operators combine decisions.
• Increment/decrement quickly adjust small values.
• Assignment operators simplify updates.
• Precedence ensures calculations happen in the right order.

This is how real games make choices thousands of times per second.

Learn Together with AI

Try these prompts:

• “Write a C++ program that checks whether a number is even or odd.”
• “Show me how to use logical operators with user input in C++.”
• “Create a C++ example demonstrating operator precedence.”

AI will help you experiment and learn faster.

Practice Challenge

Your turn!

Create a C++ program that:

• Starts with coins = 100
• Player collects 45 coins → add it
• Player spends 30 coins → subtract it
• Check:
  • hasEnoughCoins = (coins >= 50)
  • isRich = (coins >= 200)
• Print the following output:

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==============================
   COIN SYSTEM
   Coins: 115
   Has Enough Coins: true
   Is Rich: false
==============================

Use arithmetic operators, relational operators, and assignment operators.

If you’re stuck, ask AI:

“How do I compare two numbers using relational operators in C++?”

Coming Up Next

In the next lesson, you’ll learn if–else statements, how to make programs decide, just like a real game engine, cashier system, or smart device.