to increase efficiency, the amazon shipping team will group packages being shipped according to weight. they will merge a lighter package with a heavier package, which eliminates the need for separate shipments. more formally, consider n packages, where package weights[i] represents the weight of the ith package. you can combine the ith and (i 1)th package if package weights[i] < package weights[i 1], then discard the ith package. after this operation, the number of packages is reduced by 1 and the weight of the (i 1)th package increases by packageweights[i]. you can merge the packages any number of times. find the maximum possible weight of a package that can be achieved after any sequence of merge-operations.