java-algorithms/DijkstraAlgorithm.java at main · Mahidhar05/java-algorithms · GitHub

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importjava.util.Scanner;
publicclassDijkstraAlgorithm {
privatestaticvoiddijkstra(int[][] adjacencyMatrix) {
intv = adjacencyMatrix.length;
booleanvisited[] = newboolean[v];
intdistance[] = newint[v];
distance[0] = 0;
for (inti = 1; i < v; i++) {
distance[i] = Integer.MAX_VALUE;
 }
for (inti = 0; i < v - 1; i++) {

intminVertex = findMinVertex(distance, visited);
visited[minVertex] = true;

for (intj = 0; j < v; j++) {
if (adjacencyMatrix[minVertex][j] != 0 && !visited[j] &&
distance[minVertex] != Integer.MAX_VALUE) {
intnewDist = distance[minVertex] +
adjacencyMatrix[minVertex][j];
if (newDist < distance[j]) {
distance[j] = newDist;
 }
 }
 }
 }

for (inti = 0; i < v; i++) {
System.out.println(i + " " + distance[i]);
 }
 }
privatestaticintfindMinVertex(int[] distance, booleanvisited[]) {
intminVertex = -1;
for (inti = 0; i < distance.length; i++) {
if (!visited[i] && (minVertex == -1 || distance[i] <
distance[minVertex])) {
minVertex = i;
 }
 }
returnminVertex;
 }
publicstaticvoidmain(String[] args) {
Scanners = newScanner(System.in);
intv = s.nextInt();
inte = s.nextInt();
intadjacencyMatrix[][] = newint[v][v];
for (inti = 0; i < e; i++) {
intv1 = s.nextInt();
intv2 = s.nextInt();
intweight = s.nextInt();
adjacencyMatrix[v1][v2] = weight;
adjacencyMatrix[v2][v1] = weight;
 }
dijkstra(adjacencyMatrix);
 }
}