'What is the 2's complement of -17?
What will be the binary value of -17 and how to find the 2's complement of -17?
Solution 1:[1]
Assuming an 8-bit word, start with the binary form of 17. = 00010001
Then invert the bits: = 11101110
Then just add 1: = 11101111.
If you've got a 16-, 32- or 64-bit word then you'll have a load more leading 1s.
Solution 2:[2]
Even if you do not assume anything, you have to just keep the leftmost bit significant. Start with the word itself, 10001. Then invert gives the one's, 01110 Now add 1 to this number. 01111. But to keep the left most bit significant, append a one there eg,101111 in terms of the minimum number of bits required (6 here).
Sources
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Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | Trevor Tippins |
| Solution 2 | MItrajyoti Kusari |