unsigned int subtraction...

[hhhsssmmm]

Here is a simple question that im confused on...plz can someone answer it...

Im using C18 compiler....

if i use "unsigned int".... and then subtract two integers in such a way that the one which is subtracted is greater
than the one from which im subtracting...forexample...

result = small - big;

this should give me a result that does not care about the -ve sign....am i correct?....so forexample

result = 2 - 4;

the 'result ' value then contains the variable '2'.....ignoring the -ve sign

is this correct?

please can someone correct me.

thank you
Haseeb

 

[zorro]

Hi Haseeb,

Let me tell why you are wrong.
I suppose you are using 16-bit integer types.
Performing 2-4, ( 0000000000000010-0000000000000100 ) the result is 1111111111111110 . (Try the bitwise operation in order to be sure).
That result, interpreted as a signed int would be -2. But as an unsigned, it is 2^16-2=65534.
Regards

Z