meaning of cube files for HOMO and LUMO

[Ali]

Dear CP2K Users,

As a follow up to my question from yesterday, after I ran my job to
generate the HUMO and LUMO orbitals for my system I get the following
4 files. I had only asked for NHOMO 1 and NLUMO 1.

project-WFN_00176_2-1_0.cube
project-WFN_00177_1-1_0.cube
project-WFN_00177_2-1_0.cube
project-WFN_00178_1-1_0.cube

Because there are three numbers: 176,177, 178 I am not sure if the
LUMO is 178 and the HOMO is 176 (?). What is 177? What do _2-1 and
_1-1 stand for as well?

Any help will be greatly appreciated.

Is there any wisdom too to selecting the isovalue to view these?

Ali