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132 lines
3.5 KiB
JavaScript
132 lines
3.5 KiB
JavaScript
/**
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* File: graph_adjacency_matrix.js
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* Created Time: 2023-02-09
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* Author: Zhuo Qinyue (1403450829@qq.com)
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*/
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/* 基于邻接矩阵实现的无向图类 */
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class GraphAdjMat {
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vertices; // 顶点列表，元素代表“顶点值”，索引代表“顶点索引”
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adjMat; // 邻接矩阵，行列索引对应“顶点索引”
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/* 构造函数 */
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constructor(vertices, edges) {
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this.vertices = [];
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this.adjMat = [];
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// 添加顶点
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for (const val of vertices) {
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this.addVertex(val);
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}
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// 添加边
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// 请注意，edges 元素代表顶点索引，即对应 vertices 元素索引
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for (const e of edges) {
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this.addEdge(e[0], e[1]);
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}
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}
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/* 获取顶点数量 */
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size() {
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return this.vertices.length;
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}
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/* 添加顶点 */
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addVertex(val) {
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const n = this.size();
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// 向顶点列表中添加新顶点的值
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this.vertices.push(val);
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// 在邻接矩阵中添加一行
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const newRow = [];
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for (let j = 0; j < n; j++) {
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newRow.push(0);
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}
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this.adjMat.push(newRow);
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// 在邻接矩阵中添加一列
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for (const row of this.adjMat) {
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row.push(0);
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}
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}
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/* 删除顶点 */
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removeVertex(index) {
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if (index >= this.size()) {
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throw new RangeError('Index Out Of Bounds Exception');
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}
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// 在顶点列表中移除索引 index 的顶点
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this.vertices.splice(index, 1);
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// 在邻接矩阵中删除索引 index 的行
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this.adjMat.splice(index, 1);
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// 在邻接矩阵中删除索引 index 的列
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for (const row of this.adjMat) {
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row.splice(index, 1);
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}
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}
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/* 添加边 */
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// 参数 i, j 对应 vertices 元素索引
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addEdge(i, j) {
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// 索引越界与相等处理
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if (i < 0 || j < 0 || i >= this.size() || j >= this.size() || i === j) {
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throw new RangeError('Index Out Of Bounds Exception');
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}
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// 在无向图中，邻接矩阵沿主对角线对称，即满足 (i, j) == (j, i)
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this.adjMat[i][j] = 1;
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this.adjMat[j][i] = 1;
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}
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/* 删除边 */
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// 参数 i, j 对应 vertices 元素索引
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removeEdge(i, j) {
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// 索引越界与相等处理
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if (i < 0 || j < 0 || i >= this.size() || j >= this.size() || i === j) {
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throw new RangeError('Index Out Of Bounds Exception');
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}
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this.adjMat[i][j] = 0;
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this.adjMat[j][i] = 0;
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}
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/* 打印邻接矩阵 */
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print() {
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console.log('顶点列表 = ', this.vertices);
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console.log('邻接矩阵 =', this.adjMat);
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}
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}
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/* Driver Code */
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/* 初始化无向图 */
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// 请注意，edges 元素代表顶点索引，即对应 vertices 元素索引
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const vertices = [1, 3, 2, 5, 4];
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const edges = [
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[0, 1],
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[1, 2],
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[2, 3],
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[0, 3],
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[2, 4],
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[3, 4],
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];
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const graph = new GraphAdjMat(vertices, edges);
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console.log('\n初始化后，图为');
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graph.print();
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/* 添加边 */
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// 顶点 1, 2 的索引分别为 0, 2
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graph.addEdge(0, 2);
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console.log('\n添加边 1-2 后，图为');
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graph.print();
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/* 删除边 */
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// 顶点 1, 3 的索引分别为 0, 1
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graph.removeEdge(0, 1);
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console.log('\n删除边 1-3 后，图为');
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graph.print();
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/* 添加顶点 */
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graph.addVertex(6);
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console.log('\n添加顶点 6 后，图为');
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graph.print();
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/* 删除顶点 */
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// 顶点 3 的索引为 1
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graph.removeVertex(1);
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console.log('\n删除顶点 3 后，图为');
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graph.print();
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