mu 1 2 3
mu 3 2 4
mu 3 4 5
mu 3 5 6
mu 6 4 7
mu 7 5 6
mu 1 6 7
pwr 5 7 1
pwr 9 4 5
iv 5 6
mu 6 2 7
mu 7 5 2
pwr 3 3 4
iv 4 5
mu 5 1 7
mu 7 4 1