無符號與有符號

https://blog.csdn.net/u012675103/article/details/45953183?utm_source=blogxgwz6

同精度signed與unsigned比較時，轉換爲unsigned比較，轉換時以數據在內存中的表現形式轉換

int a = -1,   內存0xff ff ff ff      ->singned int->65535

 

https://blog.csdn.net/ykiwmy/article/details/78755863