Occasionally it is necessary to invert the bits for a number. Most often, this is part of custom algorithms or checksum calculations. It raises the general question: what’s the easiest way to do this?
“Bit-Flipping” can be done with the -bnot operator like this:
$number = 76
$newnumber = -bnot $number
The result shows one caveat, though:
The operator always acts on signed 64-bit numbers. A better approach may be to use the -bxor operator and provide your own bit mask that you want to flip. For a byte, the bit mask would be 0xFF, and for an Int32, it would be 0xFFFFFFFF. Here is an example to flip the bits for a byte. We padded the string representation to 8 characters to make leading zeroes visible:
$number = 76
$newnumber = $number -bxor 0xFF
The result matches:
Your learning points:
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