ProblemDescriptionOnSaintValentine'sDay,AleximaginedtopresentaspecialpendanttohisgirlfriendmadebyKkindofpearls.Thependantisactuallyastringofpearls,anditslengthisdefinedasthenumberofpearlsinit.Asisknowntoall,Alexisveryrich,andhehasNpearlsofeachkind.Pendantcanbetoldapartaccordingtopermutationofitspearls.Nowhewantstoknowhowmanykindofpendantcanhemade,withlengthbetween1andN.Ofcour...
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