Thread: Encryption cracking challenge
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Old 01-12-2020, 01:32
dila dila is offline
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-x is the same as ~x + 1

In this case the code is extracting the most-significant bit (MSB) from a and then creating a 64-bit mask from it.

If MSB(a) == 0, the result is 0x0000000000000000
Otherwise, if MSB(a) == 1, the result is 0xFFFFFFFFFFFFFFFF
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