mu 1 2 3
mu 3 2 4
mu 3 4 5
mu 3 5 6
mu 6 5 8
mu 3 8 9
mu 9 4 10 
mu 10 4 11
mu 3 11 12
mu 12 3 13
mu 13 13 2
pwr 7 4 1
iv 4 5
mu 5 2 6
mu 6 4 2
iv 3 5
mu 5 1 6
mu 6 3 1