迪杰斯特拉算法求最短路径

标签：c语言   c++   算法   

#include "iostream"
#include "memory.h"
using namespace std;

const int num = 9; //节点个数
#define Infinity 65535

void dijk(int *distance, int *p, int graphic[num][num], int source) {
	//distance记录从source到其他节点的最短距离
	bool isvisted[num]; //记录一个节点是否被访问过
	memset(p, 0, sizeof(p));  //记录在最短路径中，当前节点的父节点
	memset(isvisted, false, sizeof(isvisted));
	//初始化
	for (int i = 0; i < num; i++){
		distance[i] = graphic[source][i];
	}
	isvisted[source] = true;
	distance[source] = 0;

	for (int i = 0; i < num; i++){
		int min = Infinity;
		int index;
		//找出到source距离最短的未被访问过的节点
		for (int j = 0; j < num; j++){
			if (!isvisted[j] && distance[j] < min){
				index = j;
				min = distance[j];
			}
		}
		isvisted[index] = true;
		//修正其他节点到source的最短距离
		for (int j = 0; j < num; j++){
			if (!isvisted[j] && (min + graphic[index][j]) < distance[j]){
				distance[j] = min + graphic[index][j];
				p[j] = index;
			}
		}
	}
}

int main(){
	int graphic[num][num];
	for (int i = 0; i < num; i++)
	for (int j = 0; j < num; j++){
		if (i == j)
			graphic[i][j] = 0;
		else
		graphic[i][j] = Infinity;
	}
	graphic[0][1] = 1;
	graphic[0][2] = 5;
	graphic[1][0] = 1;
	graphic[1][2] = 3;
	graphic[1][3] = 7;
	graphic[1][4] = 5;
	graphic[2][0] = 5;
	graphic[2][1] = 3;
	graphic[2][4] = 1;
	graphic[2][5] = 7;
	graphic[3][1] = 7;
	graphic[3][4] = 2;
	graphic[3][6] = 3;
	graphic[4][1] = 5;
	graphic[4][2] = 1;
	graphic[4][3] = 2;
	graphic[4][5] = 3;
	graphic[4][6] = 6;
	graphic[4][7] = 9;
	graphic[5][2] = 7;
	graphic[5][4] = 3;
	graphic[5][7] = 5;
	graphic[6][3] = 3;
	graphic[6][4] = 6;
	graphic[6][7] = 2;
	graphic[6][8] = 7;
	graphic[7][4] = 9;
	graphic[7][5] = 5;
	graphic[7][6] = 2;
	graphic[7][8] = 4;
	graphic[8][6] = 7;
	graphic[8][7] = 4;
	int distance[num];
	int p[num];
	dijk(distance, p, graphic, 1);
	for (int i = 0; i < num; i++) {
		cout << distance[i] << endl;
	}
	return 0;
}

迪杰斯特拉算法求最短路径

标签：c语言   c++   算法   

原文地址：http://blog.csdn.net/liujan511536/article/details/42101847