带有路径打印的 Dijkstra 算法的Java程序
import java.util.Scanner; //Scanner Function to take in the Input Values
public class Dijkstra
{
static Scanner scan; // scan is a Scanner Object
public static void main(String[] args)
{
int[] preD = new int[5];
int min = 999, nextNode = 0; // min holds the minimum value, nextNode holds the value for the next node.
scan = new Scanner(System.in);
int[] distance = new int[5]; // the distance matrix
int[][] matrix = new int[5][5]; // the actual matrix
int[] visited = new int[5]; // the visited array
System.out.println("Enter the cost matrix");
for (int i = 0; i < distance.length; i++)
{
visited[i] = 0; //initialize visited array to zeros
preD[i] = 0;
for (int j = 0; j < distance.length; j++)
{
matrix[i][j] = scan.nextInt(); //fill the matrix
if (matrix[i][j]==0)
matrix[i][j] = 999; // make the zeros as 999
}
}
distance = matrix[0]; //initialize the distance array
visited[0] = 1; //set the source node as visited
distance[0] = 0; //set the distance from source to source to zero which is the starting point
for (int counter = 0; counter < 5; counter++)
{
min = 999;
for (int i = 0; i < 5; i++)
{
if (min > distance[i] && visited[i]!=1)
{
min = distance[i];
nextNode = i;
}
}
visited[nextNode] = 1;
for (int i = 0; i < 5; i++)
{
if (visited[i]!=1)
{
if (min+matrix[nextNode][i] < distance[i])
{
distance[i] = min+matrix[nextNode][i];
preD[i] = nextNode;
}
}
}
}
for(int i = 0; i < 5; i++)
System.out.print("|" + distance[i]);
System.out.println("|");
int j;
for (int i = 0; i < 5; i++)
{
if (i!=0)
{
System.out.print("Path = " + i);
j = i;
do
{
j = preD[j];
System.out.print(" <- " + j);
}
while(j != 0);
}
System.out.println();
}
}
}