you shop keeper shop assistant small nearby shop you n good ith good cost a_i coinsYou get tired remember price product customer ask decide simplify life more precisely decide set price n good haveHowever do not want lose money want choose price way sum new price sum initial price it mean sell n good new price receive great money sell initial pricesOn hand do not want lose customer big price price choose need choose minimum oneSo need find minimum possible equal price n good sell price receive great money sell initial pricesyou answer q independent query