However, I can't understand why $n is 0
Well, it's not always, at least not if I run your code and actually read from <DATA>. If there's one item in the array, it contains 0, which is the last index in the array. What do you want it to contain?

In reply to Re^3: sub routine to sort per time by moritz
in thread sub routine to sort per time by steph_bow

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