🎓 Student Management System (C++)

A console-based Student Management System written in modern C++ with support for JSON persistence, fast lookups, undo/redo functionality, and flexible search.

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🚀 Features

📌 Core functionality

• Add / delete / update students

• View all students

• Search by:

  • ID
  • Name
  • Surname
  • Full-text query (multi-word search)

⚡ Performance

• O(1) student lookup by ID using unordered_map
• Optimized deletion without shifting elements

💾 Data persistence

• Data is stored in JSON format
• Automatic load/save from file

🔄 Undo / Redo

• Full state history
• Supports reverting and reapplying actions

🔍 Advanced search

• Case-insensitive search

• Partial matches supported

• Multi-word query search:

  Jon Snow
  

  matches:

  Jon Snow
  Snow Jon
  

📊 Sorting

• Sort by:

  • ID
  • GPA
  • Age
  • Name
  • Surname

🎯 Filtering

• Filter by GPA
• Filter by age range

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🧠 Architecture

Data structures

• std::vector<Student> — main storage
• std::unordered_map<int, int> — index for O(1) access
• history / redoStack — state snapshots for undo/redo

Complexity

Operation	Complexity
Add student	O(1)
Get by ID	O(1)
Delete	O(1)
Search	O(n)
Sort	O(n log n)

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📁 Project Structure

.
├── main.cpp
├── Student.h / Student.cpp
├── StudentManager.h / StudentManager.cpp
├── students.json
└── json.hpp (nlohmann/json)

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🛠 Technologies

• C++
• STL (vector, unordered_map, algorithm)
• nlohmann/json

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▶️ How to run

1. Compile

g++ main.cpp Student.cpp StudentManager.cpp -o app

2. Run

./app

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📄 Example JSON

[
    {
        "id": 1,
        "name": "Jon",
        "surname": "Snow",
        "age": 20,
        "gpa": 4.5
    }
]

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💡 What I learned

• Working with STL containers
• Designing efficient data structures (indexing)
• Implementing undo/redo systems
• File persistence with JSON
• Writing modular and maintainable C++ code

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🔥 Future improvements

• GUI (Qt / ImGui)
• Database integration (SQLite)
• Unit tests
• CLI arguments support
• Export/import CSV

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👤 Author

GitHub: https://github.com/Skyl1te

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⭐️ If you like this project

Give it a star and feel free to contribute!