背包问题：一．　　需求分析1.本程序中，表示背包和物品的元素限定为实型，物品的多少不限（可通过改变宏选择适当的数组长度）．2.程序由用户和计算机的对话方式执行，在计算机的提示信息下由用户在键盘上输入规定的运算命令，相应的输入数据和运算结果显示在其后。3.程序执行的命令包括:1)　　构造物品数组及相应的标识数组2)　　对数组的当前状态求和3)　　打印出所有符合要求的结果4.测试数据实型的任意数据均可,不能输入字符型数据-knapsack problem : 1. A needs analysis. This procedure, said the backpack and items elements is limited to type, the number of open-items (available through Acer change the selection of appropriate length of the array). 2. Procedures by the user and computer dialogue approach to the implementation of the computer under the message by the user at the keyboard input on the operation order, the corresponding input data and computing results in the following. 3. Procedures for the implementation of the order include : 1) Construction items array and the corresponding array logo 2) to the current status of the array summation 3) Print out to meet the requirements of all four results. Test data is the type of data can be arbitrary, can not be imported for character data