12月11日,三大股指在探底之后回升,全线飘红。早盘下跌的幅度一度超过了1%,多模态、MR、游戏传媒等方向的股票上涨的幅度居前,两市上涨的个股数量将近3300只。
The output is always a String, for example H,E,L,L,O,. How could I limit the commas? I want the commas only between letters, for example H,E,L,L,O.