TSP:旅行者问题(动态规划+递归)

// TSP.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
typedef struct _node_st{
	bool inPath ;
	int nextIndex;
	_node_st():inPath(false),nextIndex(-1){
		 
	}
}Node,*NodePtr;
#define MAX 6
int dis[MAX][MAX]={
        0, 10, 20, 30, 40, 50,
        12, 0 ,18, 30, 25, 21,
        23, 19, 0, 5,  10, 15,
        34, 32, 4, 0,  8,  16,
        45, 27, 11,10, 0,  18,
        56, 22, 16,20, 12,  0
};
Node p[MAX];
void printPath();
//表示从begin开始,经过所有点后到达end的最小距离
int tsp(int beginIndex,int endIndex){

	int result = 0xFFFFFFF;
	bool isLast = true;
	for(int i=0;i<MAX;i++){

		if(i!=beginIndex){

			if(!p[i].inPath){
				isLast = false;

				p[i].inPath = true;
				
				int value = tsp(i,endIndex);
				
			
				if(dis[beginIndex][i]+value<result){

					
					p[beginIndex].nextIndex = i; 
					result = dis[beginIndex][i]+value;
			

					if(beginIndex==0&&endIndex==0){
						printPath();
					}

					
				}

				p[i].inPath = false;
				
			}

		}
	}
	if(isLast){
		
		p[beginIndex].nextIndex = endIndex;
		return dis[beginIndex][endIndex];
	}
	return result;
}
void printPath(){

	int pre = 0,next;
	int count = MAX;
	while(count--){
		next = p[pre].nextIndex;
		printf("%d->%d ",pre,next);
		pre = next;
	}
	printf("\n");
}
int main(int argc, char* argv[])
{
	//freopen("i://out.txt","w",stdout);
	p[0].inPath = true;
	printf("%d\n",tsp(0,0));
	return 0;
}

posted on 2011-10-08 21:02  yangyh  阅读(5471)  评论(2编辑  收藏  举报