Turn off the second light, the other light can only be 4, 5, 6, 7. There are four kinds.
Turn off the Three Lamps District, and the other light can only be 5, 6 and 7. There are three kinds.
Turn off the fourth light, the other light can only be 6, 7. There are two kinds.
Turn off the fifth light, and the other light can only be 7. There are 1 species.
There are 4+3+2+ 1= 10 species in total.
Mine is the simplest, and it is made according to the principle of classification and addition. Hope to adopt!