TypeScript方式实现源码
// 图的遍历算法 // 算 法 数据结构 描 述 // 深度优先搜索 栈 通过将顶点存入栈中，顶点是沿着路径被探索的，存在新的相 // 邻顶点就去访问 // 广度优先搜索 队列 通过将顶点存入队列中，最先入队列的顶点先被探索 // 当要标注已经访问过的顶点时，我们用三种颜色来反映它们的状态。 // ? 白色：表示该顶点还没有被访问。 // ? 灰色：表示该顶点被访问过，但并未被探索过。 // ? 黑色：表示该顶点被访问过且被完全探索过。 // 广度优先搜索算法会从指定的第一个顶点开始遍历图， 先访问其所有的相邻点， 就像一次访 // 问图的一层
1 class Graph {
2 vertices = [];
3 adjList = new Dictionary();
4 public addVertex(v) {
5 this.vertices.push(v);
6 this.adjList.set(v, []);
7 }
8 public addEdge(v, w) {
9 this.adjList.get(v).push(w);
10 this.adjList.get(w).push(v);
11 }
12 public initializeColor() {
13 let color = [], length = this.vertices.length;
14 for (var i = 0; i < length; i++) {
15 color[this.vertices[i]] = ‘white‘;
16 }
17 return color;
18 }
19 /**
20 * 宽度优先搜索
21 * @param v
22 * @param callback
23 */
24 public bfs(v, callback) {
25 let color = this.initializeColor(),
26 queue = new Queue();
27 queue.enqueue(v);
28 while (!queue.isEmpty()) {
29 let u = queue.dequeue(),
30 neighbors = this.adjList.get(u);
31 color[u] = ‘grey‘;
32 for (let i = 0; i < neighbors.length; i++) {
33 let w = neighbors[i];
34 if (color[w] === ‘white‘) {
35 color[w] = ‘grey‘;
36 queue.enqueue(w);
37 }
38 }
39 color[u] = ‘black‘;
40 if (callback) {
41 callback(u);
42 }
43 }
44 }
45 /**
46 * 寻找最短路径
47 * @param v
48 */
49 public BFS(v) {
50 let color = this.initializeColor(),
51 queue = new Queue(),
52 d = [],
53 pred = [];
54 queue.enqueue(v);
55 for (var i = 0; i < this.vertices.length; i++) {
56 d[this.vertices[i]] = 0;
57 pred[this.vertices[i]] = null;
58 }
59 while (!queue.isEmpty()) {
60 let u = queue.dequeue(),
61 neighbors = this.adjList.get(u);
62 color[u] = ‘grey‘;
63 for (let i = 0; i < neighbors.length; i++) {
64 let w = neighbors[i];
65 if (color[w] === ‘white‘) {
66 color[w] = ‘grey‘;
67 d[w] = d[u] + 1;
68 pred[w] = u;
69 queue.enqueue(w);
70 }
71 }
72 color[u] = ‘black‘;
73 }
74 return {
75 distances: d,
76 predecessors: pred
77 }
78 }
79 public toString() {
80 let s = ‘‘;
81 for (let i = 0; i < this.vertices.length; i++) {
82 s += this.vertices[i] + ‘ -> ‘;
83 let neighbors = this.adjList.get(this.vertices[i]);
84 for (var j = 0; j < neighbors.length; j++) {
85 s += neighbors[j] + ‘ ‘;
86 }
87 s += ‘\n‘;
88 }
89 return s;
90 }
91 }
92 var graph = new Graph();
93 var myVertices = [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘, ‘G‘, ‘H‘, ‘I‘]; //{7}
94 for (var i = 0; i < myVertices.length; i++) { //{8}
95 graph.addVertex(myVertices[i]);
96 }
97 graph.addEdge(‘A‘, ‘B‘); //{9}
98 graph.addEdge(‘A‘, ‘C‘);
99 graph.addEdge(‘A‘, ‘D‘);
100 graph.addEdge(‘C‘, ‘D‘);
101 graph.addEdge(‘C‘, ‘G‘);
102 graph.addEdge(‘D‘, ‘G‘);
103 graph.addEdge(‘D‘, ‘H‘);
104 graph.addEdge(‘B‘, ‘E‘);
105 graph.addEdge(‘B‘, ‘F‘);
106 graph.addEdge(‘E‘, ‘I‘);
107
108 console.log(graph.toString());
109
110 function printNode(value) {
111 console.log(‘Visited vertex:‘ + value);
112 }
113 graph.bfs(myVertices[0], printNode);
114
115 var shortestPathA = graph.BFS(myVertices[0]);
116 console.log(shortestPathA);
JavaScript方式实现源码
1 var Graph = (function () {
2 function Graph() {
3 this.vertices = [];
4 this.adjList = new Dictionary();
5 }
6 Graph.prototype.addVertex = function (v) {
7 this.vertices.push(v);
8 this.adjList.set(v, []);
9 };
10 Graph.prototype.addEdge = function (v, w) {
11 this.adjList.get(v).push(w);
12 this.adjList.get(w).push(v);
13 };
14 Graph.prototype.initializeColor = function () {
15 var color = [], length = this.vertices.length;
16 for (var i = 0; i < length; i++) {
17 color[this.vertices[i]] = ‘white‘;
18 }
19 return color;
20 };
21 /**
22 * 宽度优先搜索
23 * @param v
24 * @param callback
25 */
26 Graph.prototype.bfs = function (v, callback) {
27 var color = this.initializeColor(), queue = new Queue();
28 queue.enqueue(v);
29 while (!queue.isEmpty()) {
30 var u = queue.dequeue(), neighbors = this.adjList.get(u);
31 color[u] = ‘grey‘;
32 for (var i_1 = 0; i_1 < neighbors.length; i_1++) {
33 var w = neighbors[i_1];
34 if (color[w] === ‘white‘) {
35 color[w] = ‘grey‘;
36 queue.enqueue(w);
37 }
38 }
39 color[u] = ‘black‘;
40 if (callback) {
41 callback(u);
42 }
43 }
44 };
45 /**
46 * 寻找最短路径
47 * @param v
48 */
49 Graph.prototype.BFS = function (v) {
50 var color = this.initializeColor(), queue = new Queue(), d = [], pred = [];
51 queue.enqueue(v);
52 for (var i = 0; i < this.vertices.length; i++) {
53 d[this.vertices[i]] = 0;
54 pred[this.vertices[i]] = null;
55 }
56 while (!queue.isEmpty()) {
57 var u = queue.dequeue(), neighbors = this.adjList.get(u);
58 color[u] = ‘grey‘;
59 for (var i_2 = 0; i_2 < neighbors.length; i_2++) {
60 var w = neighbors[i_2];
61 if (color[w] === ‘white‘) {
62 color[w] = ‘grey‘;
63 d[w] = d[u] + 1;
64 pred[w] = u;
65 queue.enqueue(w);
66 }
67 }
68 color[u] = ‘black‘;
69 }
70 return {
71 distances: d,
72 predecessors: pred
73 };
74 };
75 Graph.prototype.toString = function () {
76 var s = ‘‘;
77 for (var i_3 = 0; i_3 < this.vertices.length; i_3++) {
78 s += this.vertices[i_3] + ‘ -> ‘;
79 var neighbors = this.adjList.get(this.vertices[i_3]);
80 for (var j = 0; j < neighbors.length; j++) {
81 s += neighbors[j] + ‘ ‘;
82 }
83 s += ‘\n‘;
84 }
85 return s;
86 };
87 return Graph;
88 }());
时间： 2024-10-22 16:47:28