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Question on simple arithmetic using perlby perlbaski (Sexton)
|on Sep 28, 2011 at 21:27 UTC||Need Help??|
perlbaski has asked for the
wisdom of the Perl Monks concerning the following question:
I ran below code with use integer line commented and uncommented.
With use integer commented: max neg num is 4294967295 error is -33
With use integer uncommented. max neg num is -2 error is -32
When I looked at integer pragma documentation, it says numbers are wrapped around after largest +ve number i.e. 2^31-1. By that logic max neg number should be -1 represented by 2^32-1.
Also, I am surprised that without integer pragma, how come I am able to see the results correctly even though it is 32 bit machine? I think its a naive question, but I am afraid I will remain naive if I dont ask it. I would like to know how such arithmetic is handled on 32 bit machines. Is there a potability issue if I write the code as above with use integer commented?
Please enlighten me!!