How do I add meshes?

General Discussion
1

border top…
border left…
border right…
border bottom…

mesh room1 = buildmesh(top+left+right+bottom)
mesh room2 = buildmesh(top_2+left_2+right_2+bottom_2)

How do I do something like this
mesh floor_plan = room1 + room2

2

Exactly like you said, minus the _ in the variables because it’s forbidden in FreeFEM language. See an example here.