graph.js

class Graph {
  constructor() {
    this.adjList = new Map();
  }

  addVertex(vertex) {
    if (!this.adjList.has(vertex)) {
      this.adjList.set(vertex, []);
    }
  }

  addEdge(vertex1, vertex2) {
    this.addVertex(vertex1);
    this.addVertex(vertex2);
    this.adjList.get(vertex1).push(vertex2);
    this.adjList.get(vertex2).push(vertex1); // Remove this for a directed graph
  }

  printGraph() {
    for (let [vertex, edges] of this.adjList.entries()) {
      console.log(`${vertex} -> ${edges.join(", ")}`);
    }
  }

  bfs(start) {
    const visited = new Set();
    const queue = [start];
    while (queue.length) {
      const vertex = queue.shift();
      if (!visited.has(vertex)) {
        console.log(vertex);
        visited.add(vertex);
        const neighbors = this.adjList.get(vertex);
        for (let neighbor of neighbors) {
          if (!visited.has(neighbor)) {
            queue.push(neighbor);
          }
        }
      }
    }
  }

  dfs(start, visited = new Set()) {
    if (visited.has(start)) return;
    console.log(start);
    visited.add(start);

    for (let neighbor of this.adjList.get(start)) {
      this.dfs(neighbor, visited);
    }
  }
}