bfs done

Author: minhaz.raufoon

Graph Theory/Breadth First Search/bfs.js

@@ -0,0 +1,59 @@
+function BFSFindShortestPath(graph, srcNode, dstNode) {
+    var isPushed = Object.create(null),
+        bfsQueue,
+        currentNode,
+        childNode,
+        parentNodeOf = Object.create(null),
+        shortestPath;
+
+    bfsQueue = [srcNode];
+    parentNodeOf[srcNode] = null;
+    isPushed[srcNode] = true;
+
+    while (bfsQueue.length > 0) {
+        currentNode = bfsQueue.shift();
+        if (currentNode === dstNode) break;
+
+        for (var i = 0; i < graph[currentNode].length; i++) {
+            childNode = graph[currentNode][i];
+            if (isPushed[childNode]) continue;
+
+            parentNodeOf[childNode] = currentNode;
+            bfsQueue.push(childNode);
+            isPushed[childNode] = true;
+        }
+    }
+
+    if (!isPushed[dstNode]) {
+        return {
+            distance: Infinity,
+            shortestPath: []
+        }
+    }
+
+    shortestPath = [dstNode];
+    currentNode = dstNode;
+
+    while (parentNodeOf[currentNode]) {
+        currentNode = parentNodeOf[currentNode];
+        shortestPath.unshift(currentNode);
+    }
+
+    return {
+        distance: shortestPath.length - 1,
+        shortestPath: shortestPath
+    }
+}
+
+
+/* TESTING */
+var graph = {
+    1: [2, 3],
+    2: [1, 3, 4, 5],
+    3: [1, 2, 4],
+    4: [2, 3, 5],
+    5: [2, 4],
+}
+var srcNode = 1, destNode = 5;
+
+console.log(BFSFindShortestPath(graph, srcNode, destNode));