Is `OrderBy(x => r.Next())` a Reliable Way to Shuffle a Collection?

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

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<法> The effectiveness of the algorithm

This algorithm is not the best random sorting method. It sorted the elements based on random numbers assigned to each element, resulting in time complexity is O (N Log N). This is much lower than the Fisher-Yates algorithm (time complexity is O (n)). <底> The underlying mechanism

The algorithm assigns a random number for each element in the collection, and then sorts the elements based on these numbers. This process effectively random the order of elements, but this is not a real random sorting operation.

<合> More suitable random sorting method

Although this method can produce random sorting results, it is not the first method because of its low efficiency. The Fisher-Yates random sorting algorithm has lower calculation complexity and higher efficiency. In addition, a special SHUFFLE expansion method can provide a clear and concise random sorting operation expression.

The implementation of the expansion method of the shuffle

To use the Fisher-Yates algorithm to implement a basic SHuffle extension method, please follow the steps below:

The input collection is converted to array. Use the predetermined function (for example,

) the element in the random exchange list.

Return to exchanges.

Using this method, developers can quickly and effectively sort the collection at the time complexity of O (N).
2. Next <能> Performance optimization
In order to further improve the performance, the expansion method can effectively exchange elements and return them in the random sorting process, thereby minimizing the time consumed by unnecessary operation.

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