code: public int transition(char c, int from)
      {
          int b = from;
          int p;
  
          p = b + (int) (c) + 1;
          if (b == check[p])
              b = base[p];
          else
              return -1;
  
          return b;
      }
docs: 转移状态
  @param c
  @param from
  @return