mu 1 2 3
mu 3 2 4
mu 3 4 5
mu 3 5 6
mu 4 5 7
mu 4 7 8
mu 6 7 9
mu 1 9 10
mu 2 8 11
mu 7 9 12
mu 1 11 13
mu 13 7 14
mu 2 9 15
mu 15 10 16
oup 11 11 16 7 9 10 14 12 3 5 8 6
echo "Classes  6B  8A  8B 10B 10D 12A 12B 13B 15A 15D 21A"