Input range should be mentioned: this kata is very performance heavy. Even the random tests only goes up to 20 elements. This information will be important to solvers.

expected:<Game(leftTeam=[Party(partySize=2, sumRating=1500.0), Party(partySize=3, sumRating=1562.0)], rightTeam=[Party(partySize=4, sumRating=1482.0), Party(partySize=1, sumRating=1523.0)])>
but was:<Game(leftTeam=[Party(partySize=3, sumRating=1562.0), Party(partySize=2, sumRating=1500.0)], rightTeam=[Party(partySize=1, sumRating=1523.0), Party(partySize=4, sumRating=1482.0)])>

expected:<Game(leftTeam=[Party(partySize=4, sumRating=1482.0), Party(partySize=1, sumRating=1523.0)], rightTeam=[Party(partySize=2, sumRating=1500.0), Party(partySize=3, sumRating=1562.0)])>
but was:<Game(leftTeam=[Party(partySize=2, sumRating=1500.0), Party(partySize=3, sumRating=1562.0)], rightTeam=[Party(partySize=4, sumRating=1482.0), Party(partySize=1, sumRating=1523.0)])>

Kata testing is seriously flawed: the parties in a team must be at the exact order, and the left and right teams must not flip with each other. Do we even care about which team is left or right, or the order of teams in the list? Maybe some people do; but none of this is mentioned in the description.

All definitions are moved to the Preloaded section.

Should be fixed now

Прикольный вариант с константой

The first 'random' case

Expected
Game(leftTeam=[Party(partySize=3, sumRating=4359.5240254169385), Party(partySize=2, sumRating=5611.560360654146)], rightTeam=[Party(partySize=1, sumRating=5065.367203992265), Party(partySize=1, sumRating=9326.666064496576), Party(partySize=1, sumRating=3404.9265711418557), Party(partySize=1, sumRating=4895.708349543196), Party(partySize=1, sumRating=1611.5804160222483)])
sum of left = 9971.084386071085
sum of right = 24304.24860519614
diff = 14333.164219125054


Actual
Game(leftTeam=[Party(partySize=3, sumRating=4359.5240254169385), Party(partySize=1, sumRating=1151.2235919993266), Party(partySize=1, sumRating=3404.9265711418557)], rightTeam=[Party(partySize=4, sumRating=4020.1198552059004), Party(partySize=1, sumRating=4895.708349543196)])
sum of left = 8915.674188558121
sum of right = 8915.828204749097
diff = 0.1540161909761082