"An explanation?"
Richard smiled after hearing Molly's words. "All right, I'll explain. It's actually very simple. The allocation problem you mentioned is like two people trying to divide a cake.
Everyone wants the bigger piece, so it's hard to satisfy both people at once. But it can be solved like this: one person is responsible for cutting the cake into two portions, while the other gets to choose which portion belongs to them first.
That way, the first person will try their best to make the two portions equal, so the second person cannot take advantage of them. The second person will try to choose the portion they believe is larger, so the first person cannot take advantage of them either. In the end, both will be satisfied.
Applied to the problem you mentioned, one side can be responsible for dividing the items of unknown value into two portions, while the other side chooses. Naturally, neither side will have any complaints."
"Uh, that does sound rather reasonable..." Molly said.
"Of course," Richard said. "This can be proven mathematically. In mathematics, the two people dividing the cake are regarded as A and B, where..."
Several dozen seconds later, after rattling off a long speech with barely a pause, Richard ignored Molly's increasingly complicated expression and continued, "Actually, dividing a cake between two people is the easiest, so long as you don't deliberately complicate the matter. Adding more people makes it a little more troublesome—three people dividing a cake, four people dividing a cake—but it still isn't too complicated.
For example, if three people are dividing a cake and you want it to be fair, it is best to introduce a fourth person as a referee. The three people dividing the cake are A, B, and C. First, place the cake on