/in/foo.cc: In function 'int main()':
/in/foo.cc:10:10: warning: unused variable 'br' [-Wunused-variable]
  int r,c,br,bc,n;
          ^~
/in/foo.cc:10:13: warning: unused variable 'bc' [-Wunused-variable]
  int r,c,br,bc,n;
             ^~
/in/foo.cc:35:26: warning: 'k' may be used uninitialized in this function [-Wmaybe-uninitialized]
              if(town[k][j]=='x')
                 ~~~~~~~~~^