/**
*
* ━━━━━━神兽出没━━━━━━
*    ┏┓   ┏┓
*   ┏┛┻━━━┛┻┓
*   ┃       ┃
*   ┃ ┗┳  ┳┛ ┃
*   ┃ ┳┛ ┗┳ ┃
*   ┃   ━   ┃
*   ┃   ┻   ┃
*   ┃       ┃
*   ┗━┓   ┏━┛Code is far away from bug with the animal protecting
*     ┃   ┃ 神兽保佑,代码无bug
*     ┃   ┃
*     ┃   ┗━━━┓
*     ┃       ┣┓
*     ┃       ┏┛
*     ┗┓┓┏━┳┓┏┛
*      ┃┫┫ ┃┫┫
*      ┗┻┛ ┗┻┛
*
* ━━━━━━感觉萌萌哒━━━━━━
*