pcylinder a 10 50
plane pp -20 0 10  1 0 0
pcylinder b1 pp 3 40
plane pp 0 -20 30  0 1 0
pcylinder b2 pp 5 40
bcut a a b1
bcut a a b2
explode a f

DT_SplitByNumber result a_1 100

checknbshapes result -t -face 99