chore: added interview question

Author: rupeshtiwari

src/data-structure/5-graph/route-between-nodes.mjs

@@ -0,0 +1,93 @@
+// unidirectional graph check if route exist between 2 given nodes.
+
+export class Graph {
+  constructor() {
+    this.nodes = new Map();
+  }
+
+  addNode(value) {
+    this.nodes.set(value, []);
+  }
+
+  addEdge(origin, destination) {
+    this.nodes.has(origin)
+      ? this.nodes.get(origin).push(destination)
+      : this.nodes.set(origin, [destination]);
+  }
+
+  getEdges(origin) {
+    return this.nodes.get(origin) || [];
+  }
+}
+
+const routes = [
+  [8, 5],
+  [8, 7],
+  [7, 11],
+  [11, 9],
+  [5, 3],
+  [5, 9],
+  [5, 10],
+  [10, 3],
+];
+
+const graph = new Graph();
+routes.forEach((r) => graph.addEdge(...r));
+
+console.log(graph);
+
+function bfs(start, end) {
+  const queue = [];
+  const visited = new Set();
+
+  queue.push(start);
+
+  while (queue.length) {
+    const node = queue.shift();
+    visit(node, visited);
+
+    if (node === end) {
+      console.log('Found ', end);
+      break;
+    }
+
+    const children = graph.getEdges(node);
+    queueChildren(children, queue, visited);1
+  }
+}
+
+function visit(node, visited) {
+  visited.add(node);
+  console.log(node);
+}
+
+function queueChildren(children, queue, visited) {
+  children.forEach((child) => {
+    if (!visited.has(child)) {
+      queue.push(child);
+    }
+  });
+}
+
+bfs(8, 9);
+
+/** TESTING
+ * end = 9, start = 8 
+ * 
+ *  visted |  queue | node
+ * ===========================
+                8   
+       8       5,7               8
+      8,5      3, 9, 10          5         
+     8,5,7   3, 9, 10,11         7
+  8,5,7,3    9, 10,11            3  
+8,5,7,3,9      10,11              9
+
+ * output
+8
+5
+7
+3
+9
+found 9
+*/