背包01动态规划

质量	价值
1	60
3	120
2	100
背包可容纳的质量	5

#pragma once

#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<stack>
using namespace std;

const int MAXSIZE = 3;


class BAGS
{
    
    
public:
	BAGS() {
    
    }
	BAGS(int i) {
    
    
		if (i == 1) {
    
    
			init();
		}
	}
	~BAGS() {
    
    }

	void init() {
    
    
		m_weight[0] = 1;
		m_value[0] = 60;
		m_weight[2] = 2;
		m_value[2] = 100;
		m_weight[1] = 3;
		m_value[1] = 120;
		
		m_bagCapcity = 5;
	}

	void getMaxValue() {
    
    
		int maxValue[10];
		fill(maxValue, maxValue + 10, 0);

		for (int i = 0; i < MAXSIZE; i++)
		{
    
    
			for (int curC = m_bagCapcity; curC >= m_weight[i]; curC--) {
    
    
				if (maxValue[curC] < maxValue[curC - m_weight[i]] + m_value[i]) {
    
    
					maxValue[curC] = maxValue[curC - m_weight[i]] + m_value[i];
					//cout<<curC << " " << maxValue[curC]<<endl;
				}
			}
		}

		cout << maxValue[m_bagCapcity] << endl;
	}
	
private:
	int m_weight[MAXSIZE], m_value[MAXSIZE];
	int m_bagCapcity;
};


void testForBag01() {
    
    
	BAGS test(1);
	test.getMaxValue();
}

1. 填表的顺序是先行后列，但列从高到低(二维转化为一维)
   
2. 原转移方程：maxValue( 前i件,bagcapacity ) =
   Max { maxValue(前i-1件,bagcapacity),
   maxValue( 前i-1件,bagcapacity-w[i] ) + v[i] }