Simple 1-dimensional labyrinth
I'm focusing on the various naming issues.



Why _nSteps? Why not simply _steps? Same for rnd instead of random, lb instead of labyrinth. The General Naming Conventions say: 


  In general, you should not use abbreviations or acronyms. These make
  your names less readable.




What kind of name is _1d_labyrinth for a namespace? The General Naming Conventions say:


  Do not use underscores, hyphens, or any other nonalphanumeric
  characters.


Also, a namespace's name should be PascalCase, so in this case OneDimensionalLabyrinth.



Why Solver1? Is there also a Solver2 and a Solver3 etc? What are their differences? Base your class name on the particulars of your class.