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pythonbit-manipulationxor

Bitwise not, can somebody explain this example?

Can somebody explain this example through binary digits?

>>> ~11
-12
Solution

  • Using 8 bit representation (you can use larger representations for the same results):

    ~11 => ~ b 00001011

    Applying NOT operator yields (1 turns to 0 and vice versa):

    ~(b 00001011) => b 11110100

    The result is negative (since the left most bit is the sign bit). To discover its value, apply 2's complement operator (see here):

    b 11110100, negate bits:
b 00001011, add 1:
+        1
----------
b 00001100 => 12

    Meaning that the result was -12.