🧮 Expression Evaluator in C++

This is a C++ project that takes a mathematical infix expression (like 2 + 3 * (4 - 1)) and:

1. Converts it to postfix (Reverse Polish Notation) format
2. Evaluates the postfix expression using a stack

It's basically how calculators or compilers handle expressions behind the scenes.

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🚀 Features

• 🔄 Infix ➡️ Postfix conversion
• 🧠 Stack-based RPN evaluation
• ✍️ Handles brackets and operator precedence
• ⚙️ Uses STL (stack, vector, string)
• 💡 Modular code with clean function design

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📸 Example

Input Expression: 2 + 2 * (1 * 2 - 4 / 2) * 1

Postfix (RPN): 2 2 1 2 * 4 2 / - * 1 * +

Evaluation Result: 0

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🛠️ How to Run

🔧 Compile:

g++ src/main.cpp -o evaluator

./evaluator
expression-evaluator/
├── README.md
└── src/
    └── main.cpp