$cycle_length being declared globally is not acceptable. I would declare $first and $second in the loop, but they're acceptable where they are.

The other issue it's very hard to spot the loop in your sub. May I recommend 

for (;;) {       # I read this as "for ever"
   ...
}

[download]

or the more popular 

while (1) {
   ...
}

[download]

In reply to Re: General style advice requested by ikegami
in thread General style advice requested by iangibson

Title:
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