[рони]

diga,

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    return a.filter(function(a) {
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document.write(fn(['P','P','Q','R'],['P','P', 'Q','Q','R'])+"<br>");
document.write(fn(['P','P', 'Q','Q','R'],['P','P','Q','R'])+"<br>");
document.write(fn(['P','P','Q','R'],['P','P', 'Q', 'p', 'Q','R', 'p'])+"<br>")
document.write(fn(['P','P', 'Q', 'p', 'Q','R', 'p'],['P','P','Q','R'])+"<br>")
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