text: class GraphUnweightedUndirected {
    // Unweighted Undirected Graph class
    constructor() {
      this.connections = {}
    }
  
    addNode(node) {
      // Function to add a node to the graph (connection represented by set)
      this.connections[node] = new Set()
    }
  
    addEdge(node1, node2) {
      // Function to add an edge (adds the node too if they are not present in the graph)
      if (!(node1 in this.connections)) {
        this.addNode(node1)
      }
      if (!(node2 in this.connections)) {
        this.addNode(node2)
      }
      this.connections[node1].add(node2)
      this.connections[node2].add(node1)
    }
  
    DFSIterative(node, value) {
      // DFS Function to search if a node with the given value is present in the graph
      const stack = [node]
      const visited = new Set()
      while (stack.length > 0) {
        const currNode = stack.pop()
        // if the current node contains the value being searched for, true is returned
        if (currNode === value) {
          return true
        }
        // adding the current node to the visited set
        visited.add(currNode)
        // adding neighbours in the stack
        for (const neighbour of this.connections[currNode]) {
          if (!visited.has(neighbour)) {
            stack.push(neighbour)
          }
        }
      }
      return false
    }
  }
  
  function main() {
    const graph = new GraphUnweightedUndirected()
    graph.addEdge(1, 2)
    graph.addEdge(2, 3)
    graph.addEdge(2, 4)
    graph.addEdge(3, 5)
    console.log(graph.DFSIterative(5, 1))
    console.log(graph.DFSIterative(5, 100))
  }
  
  main()
  