Have you looked at the code in line 25? Have you looked at the value of $PM?

The int function expects a number and warns you if it gets something that does not look like a number.

For your further understanding, hash keys can only be "strings", but Perl converts automatically between strings and numbers depending on the operators you use on the scalars containing the values.

In reply to Re: numeric hash keys by Corion
in thread numeric hash keys by AWallBuilder

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