define breadth first search code example

Example 1: breadth first search javascript

BFS(node) {
   // Create a Queue and add our initial node in it
   let q = new Queue(this.nodes.length);
   let explored = new Set();
   q.enqueue(node);

   // Mark the first node as explored explored.
   add(node);

   // We'll continue till our queue gets empty
   while (!q.isEmpty()) {
      let t = q.dequeue();

      // Log every element that comes out of the Queue
      console.log(t);

      // 1. In the edges object, we search for nodes this node is directly connected to.
      // 2. We filter out the nodes that have already been explored.
      // 3. Then we mark each unexplored node as explored and add it to the queue.
      this.edges[t]
      .filter(n => !explored.has(n))
      .forEach(n => {
         explored.add(n);
         q.enqueue(n);
      });
   }
}

Example 2: breadth first search

procedure BFS(G, start_v) is
2      let Q be a queue
3      label start_v as discovered
4      Q.enqueue(start_v)
5      while Q is not empty do
6          v := Q.dequeue()
7          if v is the goal then
8              return v
9          for all edges from v to w in G.adjacentEdges(v) do
10             if w is not labeled as discovered then
11                 label w as discovered
12                 w.parent := v
13                 Q.enqueue(w)