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XCTAssertEqual failed: ("h(t) = -16.0t^2 + 17.880t + 51.0") is not equal to ("h(t) = -16.0t^2 + 17.88t + 51.0") -
XCTAssertEqual failed: ("x(t) = 83.070t") is not equal to ("x(t) = 83.07t") -

R E A L L Y ???

Uses a lazy collection to filter and sum the multiples. This is memory efficient because it doesn't create an intermediate array.

Code is straightforward and easy to follow.

I like this clean and concise, follows Swift best practices. Simple split and map operations make it easy to understand.

Innovative use of a dictionary for transformation - great for readability and maintainability.

Efficient and direct approach without unnecessary reversals. Good readability.

Converting the string to an array is an unnecessary step since you can iterate over a string directly.

Ok, I add this to preloaded section.

Thank you for reviewing my kata and for your valuable feedback. I appreciate your point about ensuring the description is self-contained and will make the necessary updates to include a clear specification of the Trachtenberg method. You're right; multiplying by two is quite straightforward. This kata is part of a series I plan to create, focusing on more complex multiplications using the Trachtenberg method, which should be more challenging and interesting. As this is my first kata, I'm excited to explore this unique system further and share it with the community. Thanks again for your insights!

This solution is clear and concise, but it filters the entire array twice which is not optimal for large arrays.

The use of Float80 for factorial calculations may help avoid integer overflow, but it introduces potential for rounding errors. The optimization to check only up to n/2 is clever due to the symmetry of binomial coefficients; however, this could miss solutions where x is greater than n/2. Consider an iterative approach to calculate combinations, which is typically more efficient and avoids the complexities of floating-point arithmetic. Additionally, ensure the function can handle cases where the solution is on the higher side of n/2.

These expressions are clever in the sense that they compact the formulas into a single line. However without context or comments, these "magic numbers" make the code cryptic :)

This solution is very clever and uses Swift's functional programming capabilities to create an elegant one-liner. However, it can be inefficient for large numbers as it creates an infinite sequence.The solutions employ bit manipulation techniques (user8436785 and Swagger1337) are more efficient and do not suffer from the performance hit associated with large numbers.