Graph3.js

class Graph {
 constructor() {
 this.adjacencyObject = {}
 }

 addVertex(vertex) {
 if (!this.adjacencyObject[vertex]) this.adjacencyObject[vertex] = []
 }

 addEdge(vertex1, vertex2) {
 this.adjacencyObject[vertex1].push(vertex2)
 this.adjacencyObject[vertex2].push(vertex1)
 }

 removeEdge(vertex1, vertex2) {
 this.adjacencyObject[vertex1] = this.adjacencyObject[vertex1].filter(
 (v) => v !== vertex2
 )
 this.adjacencyObject[vertex2] = this.adjacencyObject[vertex2].filter(
 (v) => v !== vertex1
 )
 }

 removeVertex(vertex) {
 while (this.adjacencyObject[vertex].length) {
 const adjacentVertex = this.adjacencyObject[vertex].pop()
 this.removeEdge(vertex, adjacentVertex)
 }
 }

 /**
 * Return DFS (Depth First Search) List Using Recursive Method
 */
 DFS(start) {
 if (!start) return null

 const result = []
 const visited = {}
 const adjacencyObject = this.adjacencyObject

 function dfs(vertex) {
 if (!vertex) return null
 visited[vertex] = true
 result.push(vertex)
 adjacencyObject[vertex].forEach((neighbor) => {
 if (!visited[neighbor]) {
 dfs(neighbor)
 }
 })
 }

 dfs(start)
 return result
 }

 /**
 * Return DFS(Depth First Search) List Using Iteration
 */
 DFSIterative(start) {
 if (!start) return null

 const stack = [start]
 const visited = {}
 visited[start] = true

 const result = []
 let currentVertex

 while (stack.length) {
 currentVertex = stack.pop()
 result.push(currentVertex)

 this.adjacencyObject[currentVertex].forEach((neighbor) => {
 if (!visited[neighbor]) {
 visited[neighbor] = true
 stack.push(neighbor)
 }
 })
 }
 return result
 }

 BFS(start) {
 if (!start) return null

 const queue = [start]
 const visited = {}
 visited[start] = true

 let currentVertex
 const result = []

 while (queue.length) {
 currentVertex = queue.shift()
 result.push(currentVertex)

 this.adjacencyObject[currentVertex].forEach((neighbor) => {
 if (!visited[neighbor]) {
 visited[neighbor] = true
 queue.push(neighbor)
 }
 })
 }
 return result
 }
}

export { Graph }