The combined number of any two of the six numbers is 6×5/ 1/2= 15 groups. The conditions are the same, including 1, 2/2, 4/4, 8, 2, 1, * * 3, 15-3= 12. M, n exchange, get 12. * * * A total of 24 people. Among them, the number of identical conditions depends on observation, and there is no direct calculation method.