[GRASSweb-list]Help

[davidebraghiroli at libero.it]

Hello, I'm trying connecting contour lines resulting from a process of vectorization of a raster map.
I'm not an expert of the GIS Grass, and I need a comand that can  help me  making few lines a single one. I know that is possibl with Grass, but I don't know how to do this, and most of all without to change the topology.
Can you help me?
Davide.