/in/foo.cc: In function 'bool dfs(int, int)':
/in/foo.cc:20:60: error: invalid types 'int[int]' for array subscript
         if(prestate==1||prestate==2) return (prestate[cur-1]==1);
                                                            ^
/in/foo.cc:21:47: error: invalid types 'int[int]' for array subscript
         if(prestate==3) return (prestate[cur-1]==2);
                                               ^