chapter 11: [Graphs]

Author: loiane

examples/PacktDataStructuresAlgorithms.min.js

@@ -27,26 +27,26 @@ console.log(graph.toString());
 
 console.log('********* bfs with callback ***********');
 
-const printNode = (value) => console.log('Visited vertex: ' + value);
+const printVertex = (value) => console.log('Visited vertex: ' + value);
 
-breadthFirstSearch(graph, myVertices[0], printNode);
+breadthFirstSearch(graph, myVertices[0], printVertex);
 
 console.log('********* sorthest path - BFS ***********');
-var shortestPathA = BFS(graph, myVertices[0]);
+const shortestPathA = BFS(graph, myVertices[0]);
 console.log(shortestPathA.distances);
 console.log(shortestPathA.predecessors);
 
 //from A to all other vertices
-var fromVertex = myVertices[0];
+const fromVertex = myVertices[0];
 
-for (i = 1; i < myVertices.length; i++) {
-  var toVertex = myVertices[i],
-    path = new Stack();
-  for (var v = toVertex; v !== fromVertex; v = shortestPathA.predecessors[v]) {
+for (let i = 1; i < myVertices.length; i++) {
+  const toVertex = myVertices[i];
+  const path = new Stack();
+  for (let v = toVertex; v !== fromVertex; v = shortestPathA.predecessors[v]) {
     path.push(v);
   }
   path.push(fromVertex);
-  var s = path.pop();
+  let s = path.pop();
   while (!path.isEmpty()) {
     s += ' - ' + path.pop();
   }

examples/chapter11/02-BFS.js

@@ -2,7 +2,7 @@ const { Graph } = PacktDataStructuresAlgorithms;
 const { depthFirstSearch } = PacktDataStructuresAlgorithms;
 const { DFS } = PacktDataStructuresAlgorithms;
 
-let graph = new Graph();
+let graph = new Graph(true);
 
 let myVertices = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I'];
 
@@ -26,13 +26,13 @@ console.log(graph.toString());
 
 console.log('********* dfs with callback ***********');
 
-const printNode = value => console.log('Visited vertex: ' + value);
+const printVertex = value => console.log('Visited vertex: ' + value);
 
-depthFirstSearch(graph, printNode);
+depthFirstSearch(graph, printVertex);
 
 console.log('********* topological sort - DFS ***********');
 
-graph = new Graph();
+graph = new Graph(true); // directed graph
 
 myVertices = ['A', 'B', 'C', 'D', 'E', 'F'];
 for (i = 0; i < myVertices.length; i++) {

examples/chapter11/03-DFS.js

@@ -15,7 +15,7 @@ const initializeColor = vertices => {
 };
 
 const depthFirstSearchVisit = (u, color, adjList, callback) => {
-  color[u] = 'grey';
+  color[u] = Colors.GREY;
   if (callback) {
     callback(u);
   }

src/js/algorithms/graph/depth-first-search.js

@@ -26,7 +26,7 @@ export const prim = graph => {
     const u = minKey(graph, key, visited);
     visited[u] = true;
     for (let v = 0; v < length; v++) {
-      if (graph[u][v] && visited[v] === false && graph[u][v] < key[v]) {
+      if (graph[u][v] && !visited[v] && graph[u][v] < key[v]) {
         parent[v] = u;
         key[v] = graph[u][v];
       }

src/js/algorithms/graph/prim.js

@@ -21,9 +21,8 @@ export default class Graph {
     }
     this.adjList.get(a).push(b);
     if (!this.isDirected) {
-      // this.adjList.get(b).push(a);
+      this.adjList.get(b).push(a);
     }
-    // adjList.get(w).push(v); //commented to run the improved DFS with topological sorting
   }
   getVertices() {
     return this.vertices;