Mini Financial Ledger System

This project is a simple financial ledger written in C++. It simulates how basic banking systems manage accounts and record transactions.

The goal of this project was to understand how financial systems track deposits, withdrawals, and transfers while keeping a transaction history for each account.

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Features

• Create new accounts
• Deposit and withdraw funds
• Transfer money between accounts
• View account balance
• Maintain transaction history
• Flag unusually large transactions
• O(1) account lookup using unordered_map

Accounts are stored using unordered_map so that account lookup operations like deposits or withdrawals can be performed in constant time.

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Technologies

-C++
-STL (unordered_map, vector)
-Object-Oriented Programming

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System Design

The system is divided into three main components:

• BankSystem → handles account management and user operations
• BankAccount → stores account balance and transaction history
• Transaction → represents individual operations such as deposits or withdrawals

Architecture

User Input
    │
    ▼
BankSystem
    │
    ├── BankAccount
    │       │
    │       └── vector<Transaction>
    │
    └── Transaction

Each account maintains a vector of transactions so that operations can be recorded in the order they occur.

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Data Structures Used

unordered_map<int, BankAccount>

Used to store accounts and allow fast lookup.

vector<Transaction>

Used to maintain transaction history for each account.

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What I Learned

• Modeling real-world systems using object-oriented design
• Using STL containers to manage data efficiently
• Designing modular C++ programs

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Run

Compile:

g++ main.cpp -o ledger

Run:

./ledger