Who said some standard guessing rules?

Two people hold out a hand at the same time, with clenched fists, hold out one to five fingers, indicating numbers from zero to five, and shout out numbers from zero to 10 at the same time. If the sum of the numbers represented by two people's outstretched fingers is the same as the number shouted by one of them, then this person wins the fist. For example, if one person holds out three fingers, another person holds out four fingers, one person shouts seven, and the other person shouts six, then the person who shouts seven wins; If one person holds out a clenched fist (representing zero) and shouts three, while another person only holds out three fingers and can shout seven, then the person who shouts three wins. It's that simple. Of course, if you shout "Eight Immortals Crossing the Sea" and you only stretch out one finger, then even if the other person stretches out five fingers, it is impossible to make eight. This kind of boxing is called smelly boxing. If there is no agreement in advance, you will be fined.

Boxing style: thumb extension 1, thumb and middle finger extension 2 at the same time, thumb, index finger and middle finger extension 3, thumb, middle finger, ring finger and little finger extension 4, all extension 5.