$ perl -nle 'print "$_ is ", /^[A-Z][1-9]\.\d\d?[A-Z]*$/ ? "valid" : "invalid"' 1078942.in
A1.01A is valid
A1.01B is valid
A1.01B is valid
A2.06AA is valid
A2.06AABB is valid
A2.06B is valid
H2.25 is valid
H3.10 is valid
Imaging Center is invalid
Italy is invalid
K1.03A is valid
K1.03B is valid
R1.19G is valid
R2.25AA is valid
R2.25AABB is valid
R2.25BB is valid
R2.25D is valid
R2.25DD is valid
R2.25F is valid
R2.25FF is valid
V3.26P is valid
V3.26Q is valid
V3.26QR is valid
V3.26R is valid
V3.26R is valid
V3.26S is valid
V3.26ST is valid
V3.26T is valid