Do you mean 1+0 and 1+1?
I'm accustomed to seeing developing strengths as ratios of stock solution - water.
So 1-1 , 1+1 or 1:1 would be one part developer, one part water (half strength).
1-0 would indicate 1 part developer, zero parts water (full strength).
A good clue would be to check the times given for the different concentrations of the same developer and film/EI
If you see 1-0 is 6 minutes and 1-1 is 9 minutes, it's a safe bet the 6 minute time is full-strength.