knapsackproblem

代码说明：

   有不同重量的物品n件，求从这n件物品中任取一部分物品放入背包，使选中的物品的总重量不超过指定的限制重量，但选中物品的价值之合为最大。即任意给定物品个数及它们的重量和价值，在最大的限制重量一定的情况下，为了使价值最大，选出最优解。(There are different weights of items n pieces from n items in order to obtain any portion of the goods into the backpack, so that the total weight of the selected items does not exceed the specified weight limit, but the combined value of selected items as the greatest. That any given number of items and their weight and value limits the maximum weight of certain circumstances, in order to value the most, select the optimal solution.)