$bin[$variable][$othervariable] indexes an element with index $variable in array @bin, which contains an anonymous array reference which is indexed with $othervariable. It's the usual way of creating multi-dimensional arrays in perl.

perldata, perlreftut and perlref explain a lot.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Counting frequency of occurrence - what am I doing? by Joost
in thread Counting frequency of occurrence - what am I doing? by Annemarie

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