Remember to use warnings and strict (put it on the first lines of your code): 
use warnings;
use strict;

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In this case you will be warned that you did not properly quote your input. See Quote and Quote-like Operators in perlop for more. Good luck with your homework (and thank you for admitting that it is actually homework).
--
Andreas

In reply to Re: confused with summing certain elements from an array by andreas1234567
in thread confused with summing certain elements from an array by Anonymous Monk

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