Try putting in 8192 and you'll appreciate how much time is to be saved!

>time < nul & echo. & perl !.pl > output & time < nul & echo.
The current time is: 14:46:18.10
Enter the new time:
The current time is: 14:46:18.76
Enter the new time:
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I'd say! :)

output = (((((((((((((X0*Y0)+(X1*Y1))+((X2*Y2)+(X3*Y3)))+...
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