1. Buy shoes 45*2=90, sell 60, and lose 30.

2. Fake money, loss 100

General ledger: 130

Another algorithm:

Because the borrower and the purchase channel have no losses, then we can only use the account between the fake money and the boss:

Money earned by buying shoes:

1. Shoes: 60

2. Change: 40

General ledger: 60+40= 100

To put it bluntly, it is to turn fake money into real money.

The boss just lost two points:

1. Loss of counterfeit money 100

2.90 inches, 60 inches, 30 inches.

General ledger: 100+30= 130