The main key behind it is the use re 'eval', which allows Perl to be inside the (?{...}) considitonal regexps. Couple that with the "e" flag on s/// and it runs the loop. Now when it hits the do{}while($n), $_ is
``As`SC``Ad``S``CS`CCI``Ae``C`SI`Ed``A?``B``BIi`pI``E?``Es``C``Es``Es` +`Es``Es``Es`KI```BI``Es``Es``Es`KI``Es``Es`KI``E?``Es``Es``Es`KI``E?` +`Es``Es``Es``Es``Es`KI``E?``Es``Es``Es``Es`KI``E?``Es``C``Es``Es```BI +``Es``Es``Es`KI``Es``Es``Es`KI``Es``Es``Es`KI``E?``Ee``Ee``Es``Es``Es +``Es``Es`KI``E?``Es```BI``Es``Es``Es`KI``Es``Es`KI``E?```BI``Es``Es`` +Es`KI``Es``Es`KI``E?``Es``Es``Es``Es`KI``E?```BI``Es``Es``Es``Es`KI`` +Es``Es`KI``E?``Ee```BI``Es``Es``Es`KI``Es``Es`KI``E?``Ed``Es``Es``Es` +KI``E?``Es``C``Es``Es```BI``Es``Es``Es`KI``Es``Es``Es`KI``Es``Es``Es` +KI``E?``C``Es```BI``Es``Es``Es`KI``Es``Es`KI``Es``Es``Es``Es`KI``E?`` +Ee```BI``Es``Es``Es`KI``Es``Es`KI``E?``Ed``Es``Es``Es`KI``E?``C``Es`` +Es``Es``Es`KI``Es``Es``Es`KI``E?``Es``C``Es``Es```BI``Es``Es``Es`KI`` +Es``Es``Es`KI``Es``Es``Es`KI``E?``C```BI``Es``Es``Es``Es`KI``Es``Es`K +I``Es``Es``Es`KI``E?``Ee``Ee``Es``Es``Es``Es``Es`KI``E?``C``Ee``Es``E +s``Es`KI``Es``Es``Es`KI``E?``Ee``Ed``Es``Es``Es`KI``E?``Ee```BI``Es`` +Es``Es`KI``Es``Es`KI``E?``Ed``Es``Es``Es`KI``E?``Ed``Ee```BI``Es``Es` +`Es`KI``Es``Es``Es`KI

Hmmm, it looks like a bit of source code and a state engine to me!


In reply to Re: I refuse to explain this by strredwolf
in thread I refuse to explain this by Dominus

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