Devuwantstodecoratehisgardenwithflowers.Hehaspurchased n boxes,wherethe i-thboxcontains fi flowers.Allflowersinasingleboxareofthesamecolor(hencetheyareindistinguishable).Also,notwoboxeshaveflowersofthesamecolor.NowDevuwantstoselect exactly s flowersfromtheboxestodecoratehisgarden.Devuwouldliketoknow,inhowmanydifferentwayscanheselecttheflowersfromeachbox?Sincethisnumbermaybeverylarg...
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