mirror of
https://github.com/krahets/hello-algo.git
synced 2024-12-27 15:06:28 +08:00
127 lines
3.4 KiB
JavaScript
127 lines
3.4 KiB
JavaScript
/**
|
||
* File: graph_adjacency_list.js
|
||
* Created Time: 2023-02-09
|
||
* Author: Justin (xiefahit@gmail.com)
|
||
*/
|
||
|
||
const { Vertex } = require('../include/Vertex')
|
||
|
||
/* 基于邻接表实现的无向图类 */
|
||
class GraphAdjList {
|
||
// 邻接表,key: 顶点,value:该顶点的所有邻接顶点
|
||
adjList;
|
||
|
||
/* 构造方法 */
|
||
constructor(edges) {
|
||
this.adjList = new Map();
|
||
// 添加所有顶点和边
|
||
for (const edge of edges) {
|
||
this.addVertex(edge[0]);
|
||
this.addVertex(edge[1]);
|
||
this.addEdge(edge[0], edge[1]);
|
||
}
|
||
}
|
||
|
||
/* 获取顶点数量 */
|
||
size() {
|
||
return this.adjList.size;
|
||
}
|
||
|
||
/* 添加边 */
|
||
addEdge(vet1, vet2) {
|
||
if (!this.adjList.has(vet1) || !this.adjList.has(vet2) || vet1 === vet2) {
|
||
throw new Error("Illegal Argument Exception");
|
||
}
|
||
// 添加边 vet1 - vet2
|
||
this.adjList.get(vet1).push(vet2);
|
||
this.adjList.get(vet2).push(vet1);
|
||
}
|
||
|
||
/* 删除边 */
|
||
removeEdge(vet1, vet2) {
|
||
if (!this.adjList.has(vet1) || !this.adjList.has(vet2) || vet1 === vet2) {
|
||
throw new Error("Illegal Argument Exception");
|
||
}
|
||
// 删除边 vet1 - vet2
|
||
this.adjList.get(vet1).splice(this.adjList.get(vet1).indexOf(vet2), 1);
|
||
this.adjList.get(vet2).splice(this.adjList.get(vet2).indexOf(vet1), 1);
|
||
}
|
||
|
||
/* 添加顶点 */
|
||
addVertex(vet) {
|
||
if (this.adjList.has(vet)) return;
|
||
// 在邻接表中添加一个新链表
|
||
this.adjList.set(vet, []);
|
||
}
|
||
|
||
/* 删除顶点 */
|
||
removeVertex(vet) {
|
||
if (!this.adjList.has(vet)) {
|
||
throw new Error("Illegal Argument Exception");
|
||
}
|
||
// 在邻接表中删除顶点 vet 对应的链表
|
||
this.adjList.delete(vet);
|
||
// 遍历其它顶点的链表,删除所有包含 vet 的边
|
||
for (let set of this.adjList.values()) {
|
||
const index = set.indexOf(vet);
|
||
if (index > -1) {
|
||
set.splice(index, 1);
|
||
}
|
||
}
|
||
}
|
||
|
||
/* 打印邻接表 */
|
||
print() {
|
||
console.log("邻接表 =");
|
||
for (const [key, value] of this.adjList) {
|
||
const tmp = [];
|
||
for (const vertex of value) {
|
||
tmp.push(vertex.val);
|
||
}
|
||
console.log(key.val + ": " + tmp.join());
|
||
}
|
||
}
|
||
}
|
||
|
||
if (require.main === module) {
|
||
/* Driver Code */
|
||
/* 初始化无向图 */
|
||
const v0 = new Vertex(1),
|
||
v1 = new Vertex(3),
|
||
v2 = new Vertex(2),
|
||
v3 = new Vertex(5),
|
||
v4 = new Vertex(4);
|
||
const edges = [[v0, v1], [v1, v2], [v2, v3], [v0, v3], [v2, v4], [v3, v4]];
|
||
const graph = new GraphAdjList(edges);
|
||
console.log("\n初始化后,图为");
|
||
graph.print();
|
||
|
||
/* 添加边 */
|
||
// 顶点 1, 2 即 v0, v2
|
||
graph.addEdge(v0, v2);
|
||
console.log("\n添加边 1-2 后,图为");
|
||
graph.print();
|
||
|
||
/* 删除边 */
|
||
// 顶点 1, 3 即 v0, v1
|
||
graph.removeEdge(v0, v1);
|
||
console.log("\n删除边 1-3 后,图为");
|
||
graph.print();
|
||
|
||
/* 添加顶点 */
|
||
const v5 = new Vertex(6);
|
||
graph.addVertex(v5);
|
||
console.log("\n添加顶点 6 后,图为");
|
||
graph.print();
|
||
|
||
/* 删除顶点 */
|
||
// 顶点 3 即 v1
|
||
graph.removeVertex(v1);
|
||
console.log("\n删除顶点 3 后,图为");
|
||
graph.print();
|
||
|
||
}
|
||
|
||
module.exports = {
|
||
GraphAdjList
|
||
};
|