2021-01-06 17:13:52 -03:00
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// https://en.wikipedia.org/wiki/Neighbourhood_(graph_theory)
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2021-01-06 17:37:19 -03:00
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class Graph {
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2021-01-06 17:10:09 -03:00
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// Generic graph: the algorithm works regardless of direction or weight
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2021-01-06 17:37:19 -03:00
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constructor () {
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2021-01-06 17:10:09 -03:00
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this.edges = []
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}
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2021-01-06 17:37:19 -03:00
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addEdge (node1, node2) {
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// Adding edges to the graph
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this.edges.push({
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node1,
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node2
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})
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}
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2021-01-06 17:37:19 -03:00
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nodeNeighbors (node) {
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// Returns an array with all of the node neighbors
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2021-01-17 01:11:13 -03:00
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const neighbors = new Set()
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2021-01-18 20:56:58 -03:00
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for (const edge of this.edges) {
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// Checks if they have an edge between them and if the neighbor is not
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// already in the neighbors array
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2021-01-18 20:54:44 -03:00
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if (edge.node1 === node && !(neighbors.has(edge.node2))) {
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neighbors.add(edge.node2)
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} else if (edge.node2 === node && !(neighbors.has(edge.node1))) {
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neighbors.add(edge.node1)
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2021-01-06 17:10:09 -03:00
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}
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}
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return neighbors
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}
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}
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(() => {
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2021-01-06 17:37:19 -03:00
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const graph = new Graph()
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2021-01-06 17:10:09 -03:00
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graph.addEdge(1, 2)
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graph.addEdge(2, 3)
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graph.addEdge(3, 5)
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graph.addEdge(1, 5)
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console.log(graph.nodeNeighbors(1))
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})()
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