Assign similar name to a group

I want to set Mark parameter ST1 and ST2 two group of steel members.

i know it will be done through level or flattening the lists.

but unable to find the solution.

please help

Elements set parameter error?
what is showing?
May be try with cross product

@_Vijay thanks for replying

can u please help me do it.

I know i can do by
for i in range 1 to count(here in this case 2)
and then create two lists

but i dont know how to implement this

i dont know how to use cross product for this.

i have done some modifications, still cannot reach at my goal.

Like this? i did not understand fully.

Cycle.dyn (20.5 KB)

@_Vijay please help me to solve this too.

why warning is generated while setting parameter value

Mark value.dyn (17.2 KB)