Is Using `Random` and `OrderBy` an Efficient Way to Shuffle a List?

Use

and shuffle list: Is it an efficient algorithm? Random OrderBy This article discusses whether the use of and

is an effective way to shuffle list.

Random Method OrderBy

The code provided to generate a random number for each element, and resume the list based on these numbers:

Evaluation

<code>var r = new Random();
var shuffled = ordered.OrderBy(x => r.Next());</code>

Although this method looks very intuitive, it has some shortcomings:

Computing complexity:

The time complexity is O (N Log N), which is inefficient for large lists. The better shuffle algorithm has the complexity of O (N).

Potential problems:

Based on random numbering elements may cause deviation shuffling, the frequency of certain elements may be higher than other elements.
• alternative
• The better shuffle algorithm is the Fisher-Yates shuffle, which exchanges the element to a random position in the list. This provides a more uniform distribution, and the complexity is O (n).
Implement

This expansion method simplifies the use of Fisher-Yates' shuffle and avoids the needs of generating new arrays.

Conclusion

and can be used for shuffling, but they have the problem of efficiency and deviation. Fisher-Yates shuffle provides a more efficient and non-deviating solution, which is the first choice in most applications that need to be shuffled.

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