You don't need the structure in order to find the oxidation number/state of each sulfur atom.
Anyway, it looks like this:
You do need the structure to find the oxidation number/state of each sulfur atom.
Without the structure, you would be calculating average oxidation state of all sulphur atoms put together.
For instance, in this structure, the 2 S-atoms in the center have 0 oxidation state, while those at the ends have +5 state.
But without the structure, one would say that the oxidation state on each sulphur atom is +10/4 = +5/2