C++ Programming Portfolio

A collection of C++ applications ranging from basic utility tools to game logic and algorithmic implementations. This repository demonstrates core programming concepts including arrays, functions, conditional logic, and randomized algorithms.

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Project Categories

1. Games

• Tic-Tac-Toe (Smart AI): A complete game featuring an AI that uses a "Sum-Difference" mathematical approach to identify winning moves and block player threats.
• Rock Paper Scissors: A classic game implementing randomized computer choices and a replay system.
• Number Guessing Game: A terminal-based game where the user must guess a randomly generated number within a specified range.

2. Algorithms

• Credit Card Validator: An implementation of the Luhn Algorithm used to validate credit card numbers through digit reversal, doubling alternate digits, and modulo 10 checksums.

3. Financial & Utility Tools

• Banking Practice Program: A simulation of a bank teller system with functionalities for balance inquiry, deposits, and withdrawals, including basic input validation.
• Temperature Converter: A tool to convert values between Celsius and Fahrenheit using standard conversion formulas.
• Random Event Generator: A program that simulates a prize drawing using a switch-case structure and randomized integers.

4. Mathematical Fundamentals

• Calculator: A basic arithmetic tool for addition, subtraction, multiplication, and division.
• Hypotenuse Calculator: A geometry utility that uses the Pythagorean theorem ($a^2 + b^2 = c^2$) to calculate the third side of a right-angled triangle.

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Technical Highlights

Tic-Tac-Toe AI Logic

The AI in the Tic-Tac-Toe project follows an Offense > Defense > Random priority system:

1. Offense: Scans for any row, column, or diagonal where it has two pieces and an empty spot to win the game.
2. Defense: Scans for player threats where the player has two pieces in a line and blocks the third spot.
3. Sum-Difference Math: To identify the target move, the code calculates the sum of the indices in a winning line (e.g., $0+1+2=3$) and subtracts the occupied indices to find the exact remaining coordinate.

Technical Highlights (v2.0) -- TIC-TAC-TOE

• Strategic AI: Now prioritizes the center square and corners to secure a stronger board position.
• Randomized Starts: Implemented a coin-flip mechanic to decide the starting player.
• Advanced Board Scanning: Replaced move counters with a full-board state scanner (chk function) for more accurate tie detection.

Credit Card Validation (Luhn Algorithm)

The validator implements the following steps to verify card authenticity:

1. Reverses the credit card number string.
2. Doubles every second digit from the right.
3. If doubling results in a number greater than 9, subtracts 9 from the result.
4. Sums all digits and checks if the total is divisible by 10.

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How to Run

To compile and run any of these projects, use a C++ compiler such as g++:

1. Open your terminal.
2. Navigate to the folder containing the file.
3. Compile the code:

   g++ FileName.cpp -o ProgramName

4. Execute the file:

5. ./ProgramName