Python 踩坑 --- 负数能无限右移?? - V2EX
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mullenlee

Python 踩坑 --- 负数能无限右移??

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  •   mullenlee Apr 19, 2019 2715 views
    This topic created in 2564 days ago, the information mentioned may be changed or developed.

    如图:代码尝试打印-1 的二进制形式,发现-1 竟然能无限右移??

    >>并非循环移位操作啊

    本菜鸟拜求大佬解答 !

    3 replies    2019-04-19 22:42:28 +08:00
    geelaw
        1
    geelaw  
       Apr 19, 2019 via iPhone
    有些语言对负数右移是未定义,有的是算术移位,有的是循环移位。

    算术移位+补码表示 就会出现不断右移任意负数都会得到 -1 的现象。
    mullenlee
        2
    mullenlee  
    OP
       Apr 19, 2019
    @geelaw 谢谢
    Procumbens
        3
    Procumbens  
       Apr 19, 2019
    算术右移本来就是这样的。
    符号数的最高位符号位为 1 Arithmetic shift 就是右移后高位由符号位填充。所以-1 右移的结果一直是-1
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