  - 2

(  ,   ,     ).

         
 . 

 
      N -    
(1<=N<=100).     (0   ,
1 -  ).      -   .

 
      -   ( , 
 ).
   ,    -1.

  
5
0 1 0 0 1
1 0 1 0 0
0 1 0 0 0
0 0 0 0 0
1 0 0 0 0
4 5

  
-1
