活动选择的贪心算法与动态规划（未完成）

Posted 2020-09-09 lineaar

// greedy_algorithm.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include<iostream>
#include<queue>
using namespace std;

#define NofActivity 11
int c[NofActivity + 1][NofActivity + 1];
int reme[NofActivity + 1][NofActivity + 1];
//活动的结构/////////////////////////////////////////
struct Activity
{
	int num;
	int start;
	int finish;
};

Activity Act[12] = { {0,0,0},{ 1,1,4 },{2,3,5 },{3, 0,6 },{4, 5,7 },{5, 3,9 },{6, 5,9 },{7, 6,10 },{8, 8,11 },{9, 8,12 },{10, 2,14 },{11, 12,16 }};

///用队列来存储符合条件的活动，递归版本
queue<Activity> select;
void Recursive_activity_selector(Activity* Act, int k, int n)
{
	int m = k + 1;
	while (m <= n&&Act[m].start < Act[k].finish)
		m++;
	if (m <= n)
	{
		select.push(Act[m]);
		Recursive_activity_selector(Act, m, n);
	}
}

///活动选择的迭代版本//////////////////////
void Greedy_activity_selector(Activity* Act)
{
	int n = NofActivity;
	while (!select.empty())select.pop();
	select.push(Act[1]);
	int k = 1;
	for (int i = 2; i <= n; i++)
	{
		if (Act[i].start > Act[k].finish) {
			select.push(Act[i]);
			k = i;
		}
	}
}

/////活动选择的动态规划版本//////////////////////////////////
void activity_selector(Activity* Act)
{
	queue<int> que;
	for (int i = 0; i <= NofActivity; i++)
	{
		c[i][i] = 0;
		c[0][i] = 0;
		c[i][0] = 0;
	}
	for(int l=2;l<=NofActivity;l++)
		for (int i = 1; i <= NofActivity-l+1; i++)
		{
			int j = i + l - 1;
			int m = i + 1;
			while (m <= j&&Act[m].start < Act[i].finish)
				m++;
			if (m > j)c[i][j] = 0;
			else
			{
				int temp = c[i][i];
				reme[i][j] = i;
				for(int k=i+1;k<=j;k++)
					if (c[i][k] + c[k][j] + 1 > temp)
					{
						temp = c[i][k] + c[k][j] + 1;
						reme[i][j] = k;
					}
				c[i][j] = temp;
			}
		}

	
}


int main()
{
	//Recursive_activity_selector(Act, 0, NofActivity);
	/*
	Greedy_activity_selector(Act);
	while (!select.empty())
	{
		cout << select.front().num<< ‘\t‘;
		select.pop();
	}
	*/
	activity_selector(Act);
	for (int i = 1; i <= NofActivity; i++) {
		for (int j = 1; j <= NofActivity; j++)
			cout << c[i][j] << ‘ ‘;
		cout << endl;
	}
	while (1);
    return 0;
}