I don't think either explanation above is terribly clear, so I'll expound a little. You are getting bitten by order of operations. As described in Terms and List Operators (Leftward), 
print ($foo & 255) + 1, "\n";

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probably doesn't do what you expect at first glance. The parentheses enclose the argument list for print which is evaluated (printing the result of $foo & 255 ). Then one is added to the return value of print (usually 1). The result is something like this: 
1 + 1, "\n"; # Obviously not what you meant.

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To do what you meant properly, you must write: 
print(($foo & 255) + 1, "\n");

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Your code 
print (1-1/2000)**$i;

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is functionally equivalent to 
(print (1-1/2000))**$i;

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and not 
print ((1-1/2000)**$i);

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as you might think. The parentheses bind tighter to the print than to the exponentiation operator.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: strange arithmetic by kennethk
in thread strange arithmetic by morgon

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