I'll assume your arrays contain a single character per element, though that's unclear from your description. 
while(@lines1 > 0 and @lines2 > 0) {
    last if shift(@lines1) ne shift(@lines2);
}
print "*\n" if @lines1 > 0 or @lines2 > 0;

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Makeshifts last the longest.

In reply to Re: comparing strings by Aristotle
in thread comparing strings by Anonymous Monk

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