62 lines
1.7 KiB
JavaScript
62 lines
1.7 KiB
JavaScript
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(function (exports) {
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'use strict';
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var topologicalSort = (function () {
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function topologicalSortHelper(node, visited, temp, graph, result) {
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temp[node] = true;
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var neighbors = graph[node];
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for (var i = 0; i < neighbors.length; i += 1) {
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var n = neighbors[i];
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if (temp[n]) {
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throw new Error('The graph is not a DAG');
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}
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if (!visited[n]) {
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topologicalSortHelper(n, visited, temp, graph, result);
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}
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}
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temp[node] = false;
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visited[node] = true;
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result.push(node);
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}
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/**
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* Topological sort algorithm of a directed acyclic graph.<br><br>
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* Time complexity: O(|E| + |V|) where E is a number of edges
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* and |V| is the number of nodes.
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*
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* @public
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* @module graphs/others/topological-sort
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* @param {Array} graph Adjacency list, which represents the graph.
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* @returns {Array} Ordered vertices.
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*
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* @example
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* var topsort =
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* require('path-to-algorithms/src/graphs/' +
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* 'others/topological-sort').topologicalSort;
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* var graph = {
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* v1: ['v2', 'v5'],
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* v2: [],
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* v3: ['v1', 'v2', 'v4', 'v5'],
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* v4: [],
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* v5: []
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* };
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* var vertices = topsort(graph); // ['v3', 'v4', 'v1', 'v5', 'v2']
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*/
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return function (graph) {
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var result = [];
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var visited = [];
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var temp = [];
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for (var node in graph) {
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if (!visited[node] && !temp[node]) {
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topologicalSortHelper(node, visited, temp, graph, result);
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}
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}
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return result.reverse();
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};
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}());
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exports.topologicalSort = topologicalSort;
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}(typeof exports === 'undefined' ? window : exports));
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