Skoder Skoder - 1 month ago 9
C# Question

Generate N random and unique numbers within a range

What is an efficient way of generating N unique numbers within a given range using C#? For example, generate 6 unique numbers between 1 and 50. A lazy way would be to simply use

Random.Next()
in a loop and store that number in an array/list, then repeat and check if it already exists or not etc.. Is there a better way to generate a group of random, but unique, numbers?
To add more context, I would like to select N random items from a collection, using their index.

thanks

Answer

Take an array of 50 elemwnts: {1, 2, 3, .... 50} Shuffle the array using any of the standard algorithms of randomly shuffling arrays. The first six elements of the modified array is what you are looking for. HTH

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