diff --git a/Graphs/KruskalMST.js b/Graphs/KruskalMST.js
new file mode 100644
index 0000000000..0a09c631ba
--- /dev/null
+++ b/Graphs/KruskalMST.js
@@ -0,0 +1,115 @@
+class DisjointSetTreeNode {
+ // Disjoint Set Node to store the parent and rank
+ constructor (key) {
+ this.key = key
+ this.parent = this
+ this.rank = 0
+ }
+}
+
+class DisjointSetTree {
+ // Disjoint Set DataStructure
+ constructor () {
+ // map to from node name to the node object
+ this.map = {}
+ }
+
+ makeSet (x) {
+ // Function to create a new set with x as its member
+ this.map[x] = new DisjointSetTreeNode(x)
+ }
+
+ findSet (x) {
+ // Function to find the set x belongs to (with path-compression)
+ if (this.map[x] !== this.map[x].parent) {
+ this.map[x].parent = this.findSet(this.map[x].parent.key)
+ }
+ return this.map[x].parent
+ }
+
+ union (x, y) {
+ // Function to merge 2 disjoint sets
+ this.link(this.findSet(x), this.findSet(y))
+ }
+
+ link (x, y) {
+ // Helper function for union operation
+ if (x.rank > y.rank) {
+ y.parent = x
+ } else {
+ x.parent = y
+ if (x.rank === y.rank) {
+ y.rank += 1
+ }
+ }
+ }
+}
+
+class GraphWeightedUndirectedAdjacencyList {
+ // Weighted Undirected Graph class
+ constructor () {
+ this.connections = {}
+ this.nodes = 0
+ }
+
+ addNode (node) {
+ // Function to add a node to the graph (connection represented by set)
+ this.connections[node] = {}
+ this.nodes += 1
+ }
+
+ addEdge (node1, node2, weight) {
+ // Function to add an edge (adds the node too if they are not present in the graph)
+ if (!(node1 in this.connections)) { this.addNode(node1) }
+ if (!(node2 in this.connections)) { this.addNode(node2) }
+ this.connections[node1][node2] = weight
+ this.connections[node2][node1] = weight
+ }
+
+ KruskalMST () {
+ // Kruskal's Algorithm to generate a Minimum Spanning Tree (MST) of a graph
+ // Details: https://en.wikipedia.org/wiki/Kruskal%27s_algorithm
+ // getting the edges in ascending order of weights
+ const edges = []
+ const seen = new Set()
+ for (const start of Object.keys(this.connections)) {
+ for (const end of Object.keys(this.connections[start])) {
+ if (!seen.has(`${start} ${end}`)) {
+ seen.add(`${end} ${start}`)
+ edges.push([start, end, this.connections[start][end]])
+ }
+ }
+ }
+ edges.sort((a, b) => a[2] - b[2])
+ // creating the disjoint set
+ const disjointSet = new DisjointSetTree()
+ Object.keys(this.connections).forEach(node => disjointSet.makeSet(node))
+ // MST generation
+ const graph = new GraphWeightedUndirectedAdjacencyList()
+ let numEdges = 0
+ let index = 0
+ while (numEdges < this.nodes - 1) {
+ const [u, v, w] = edges[index]
+ index += 1
+ if (disjointSet.findSet(u) !== disjointSet.findSet(v)) {
+ numEdges += 1
+ graph.addEdge(u, v, w)
+ disjointSet.union(u, v)
+ }
+ }
+ return graph
+ }
+}
+
+function main () {
+ const graph = new GraphWeightedUndirectedAdjacencyList()
+ graph.addEdge(1, 2, 1)
+ graph.addEdge(2, 3, 2)
+ graph.addEdge(3, 4, 1)
+ graph.addEdge(3, 5, 100) // Removed in MST
+ graph.addEdge(4, 5, 5)
+ console.log(graph)
+ console.log(graph.KruskalMST())
+}
+
+main()
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