How is the memory representation of signed and unsigned no:s in C?

how operators can be used for both signed and unsigned no:s?

How is the memory representation of signed and unsigned no:s in C?
Singed integers are typically represented with two's complement representation. To represent a negative number, take the complement of the positive equivalent and add 1:





Consider these 8-bit numbers:





-18 = ~(00010010) + 1


= 11101101 + 1


= 11101110





Now if you want to subtract 18 from 23, you can simply use addition and two's complement:





23 = 00010111


-18 = 11101110


---------------------


5 = 00000101





Overflow is ignored.





Now, for floating point numbers, that's a whole different story.

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