This looks to be the discrete random variable problem with the alias method: https://en.wikipedia.org/wiki/Alias_method https://en.wikipedia.org/wiki/Alias_met

This looks to be the discrete random variable problem with the alias method: https://en.wikipedia.org/wiki/Alias_method https://en.wikipedia.org/wiki/Alias_method but they don't seem to reduce each choice (1-10) to just two options.