Say i have this planer graph
as we can see it has total 8 edges and 3 regions.
Now degree of a region is the number of edges bordering that region. So what i do not understand is that how we are actually finding it cause according to me
deg(r2) = 7 since there is an edge below (the single one going diagonally) but in the answers its given.
deg(r1)=3
deg(r2)=6
deg(r3)=7
So how do we actually find the number of degrees of a certain region.