~~~~...~0~~7 
~~~~~......~7 
7..~~....~0~  
7.~.~~.0~~~   
7.~....~7~7   
70.~~....~7   
 7~~....~.7   
   7.....<77  
   7~.~~...7  
   77.~..0~~.7
    7.~..~~~~7
    77~.~.~~~7
     77777~777
          77