n=20;
m=10;
k=1;
tube=[|18,1,6|];
X=[6,8,6,7,6,6,6,7,9,5,5,9,9,9,8,8,9,3,5,9];
Y=[9,4,3,7,6,8,5,8,9,2,2,7,4,8,1,7,3,1,4,1];