1. Input points 

format:
it contains 3N lines(N points)
line 3i+1: coordinates of the point
line 3i+2: estimated normal of the point
line 3i+3: 10 nearest neighbors index(indices start from 0)
eg:
0.1 0.2 0.15
-1.0 0.0 0.0
5 2 18 20 3 23 45 4 59 9



2. Voronoi vertices 

format:
it contains 2M lines(M Voronoi points)
line 2i+1: coordinates of the Voronoi point
line 2i+2: 10 nearest neighbors of the normal points



3. Delaunay triangles and dual Voronoi edges

format:
it contains 2K lines(K Delaunay triangles)
line 2i+1: the indices of three vertices of a triangle
line 2i+2: the endpoints of the corresponding Voronoi edges
eg:
0 14 21(normal point index)
4 3(voronoi point index)


Although some Voronoi edge is infinite, we artifically
create an endpoint far away from the model. 



4. Output file

It contains P lines(P restricted Delaunay triangles)
every lines is just three indices of the triangle vertices.