Mathematical No-risk Trade Resolution Tool

This is a tool to help resolve the "mathematical" or no-risk trade lists used on boardgamegeek.

See: How no-risk trades work, How this tool works



How No-risk Trade Lists Work

How to use this resolution tool

In the text box below, list each person and their preferences on one line. List each persons username (removing any spaces) followed by a space separated list of the usernames of the offerers they are interested in, in order. For example, if Matthew is interested in the offer of Scott or Derk, Derk is interested in the offer of Brett or Alan, Scott is interested in the offer of Derk only, Brett is interested in the offer of Alan, Matthew or Rick, Rick is interested in the offer of Alan, and Alan is interested in the offer of Matthew, Scott, Rick, Brett or Derk, in order, you'd enter:
Matthew Scott Derk
Derk Brett Alan
Scott Derk
Brett Alan Matthew Rick
Rick Scott
Alan Matthew Scott Rick Brett Derk                                                                                                                                                                    
This would result in Derk sending to Scott who sends to Matthew who sends to Alan who sends to Brett who sends to Derk. Everyone is happy, except maybe Rick, but he didn't gain or lose anything. Sometimes, due to exact ties (exact same number of rankings with the same relative rankings) there may be ambiguity, in which case one outcome is selected randomly. In this case, I recommend running it a few times (hitting reload after submitting is sufficient) and choosing the outcome that yields the most trades, but this is rare.

The current default (and most popular) algorithm is the "Maximize Trades" algorithm. A lot of people have been curious how it works, so I have a poorly written description of how it works.