[FE]: Code challenge solution - Lucasta To

[LucastaTo]

Overview

This PR completes all three tasks of the coding challenge, covering algorithm implementation, frontend development, and React performance optimization.

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Problem 1: Summation Function

• Implemented sum_to_n(n) using three different approaches:
  • Iterative (loop)
  • Recursive
  • Mathematical formula (O(1))
• Ensured correctness and readability across implementations

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Problem 2: Currency Swap UI

• Built an interactive currency swap interface
• Features:
  • Token selection with icons
  • Real-time exchange rate calculation using external API
  • Input validation and error handling
  • Responsive and user-friendly design
• Focused on clean UI/UX and maintainable code structure

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Problem 3: React Code Analysis & Refactor

• Identified performance issues and anti-patterns:
  • Unnecessary re-renders
  • Inefficient state and effect usage
  • Suboptimal component structure
• Refactored code to:
  • Improve performance
  • Follow React best practices
  • Enhance readability and maintainability

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Notes

• Code is structured for clarity and scalability
• Additional comments are included where necessary to explain decisions