说明：  该程序用动态规划解决经典的背包问题,虽然它的效率与分支定界法比起来,还是有一定的差距,但它的简洁性却是无与伦比的.
(the program with dynamic programming solution to the classic knapsack problem, although its efficiency and branch and bound over, there is still a certain gap, but its simplicity is incomparable.)