背包动态规划输入

Question

我想知道对于背包问题是否有任何具体的问题和答案，我可以输入和修改此代码以确保我正确地完成了它？我正在尝试进入动态编程并从这个问题开始，但无法知道它是否真的在没有输入的情况下工作 - 我在一些电源点上发现了一些案例，虽然我的代码输出正确的信息，但它们很漂亮基本和简单的案例，所以我想确保这适用于更多的输入。

这是我的代码：

import java.util.ArrayList;

public class Knapsack {

    private int numThings = 0;

    public static void main(String[] args) {

        (new Knapsack()).run();
    }

    public void run() {

        ArrayList<Thing> thingList = new ArrayList<Thing>();
        thingList.add(new Thing(60, 2));
        thingList.add(new Thing(75, 3));
        thingList.add(new Thing(90, 4));


        int maxWeight = 5;


        int[] vals = new int[maxWeight + 1];
        vals[2] = 60;

        Thing nullThing = new Thing(0,0);
        Thing max;
        int maxSet = 0;

        for (int i = 1; i < vals.length; i++) {// lets go through weights leading up to our maximal weight

            System.out.println(i);
            max = nullThing;
            for (Thing x : thingList) {

                if ((i-x.getWeight() >= 0) && (x.getValue() + vals[i-x.getWeight()] > max.getValue() + vals[i-max.getWeight()])) {

                    max = x;
                    maxSet = 1;//here, we compare possibilities of adding items by subtracting weights from  our current index and seeing which ones produce the highest values
                }
            }

            if (maxSet == 1) {

                vals[i] = max.getValue() + vals[i-max.getWeight()];
                System.out.println(max.info() );//if we find something that sets a highest value, we cache that info into the array for future use
            }
        }

        System.out.println(vals[maxWeight]);


    }


    private class Thing {

        private int value, weight;

        public Thing(int v, int w) {

            value = v;
            weight = w;

        }

        public int getValue() {

            return value;
        }

        public int getWeight() {

            return weight;
        }

        public String info() {

            return "I have a weight of "+weight+" and a value of "+ value;
        }
    }
}

Answer 1

谷歌搜索“背包问题数据集”会产生大量答案。 Here is first.