# -*- coding: rot13 -*-
vzcbeg onfr64, gvzr, flf
sebz vgregbbyf vzcbeg vmvc, plpyr
qrs o3(p):erghea onfr64.o32rapbqr(p)
qrs erirefr(p):erghea p[::-1]
qrs kbe(o):erghea ''.wbva([pue(beq(k)^beq(l)) sbe k,l va vmvc(o, erirefr(o))])
qrs g(e):erghea gvzr.gvzr().fcyvg('.')[0][:4]
iny = flf.neti[1]
cevag erirefr(kbe(o3(iny))).rapbqr('hex')