输入外挂

int read()  {      int res = 0, ch, flag = 0;        if((ch = getchar()) == '-')             //判断正负          flag = 1;        else if(ch >= '0' && ch <= '9')           //得到完整的数          res = ch - '0';      while((ch = getchar()) >= '0' && ch <= '9' )          res = res * 10 + ch - '0';        return flag ? -res : res;  }