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import java.util.*; public class UnionFind { int parent[] ; public UnionFind(int n){ parent = new int[n]; for(int i = 0; i < n; i++){ parent[i] = i; } } public int find(int x){ if(parent[x] != x){ parent[x] = find(parent[x]); } return parent[x]; } public void union(int x, int y){ int rootX = find(x); int rootY = find(y); if(rootX != rootY){ parent[rootX] = rootY; } } public static void main(String[] args){ List> disJointGraph = new ArrayList<>(); for(int i = 0; i < 5; i++){ disJointGraph.add(new ArrayList<>()); } disJointGraph.get(0).add(1); disJointGraph.get(1).add(2); disJointGraph.get(3).add(4); System.out.println("Graph representation:"); for(int i = 0; i < disJointGraph.size(); i++){ for(int neighbor : disJointGraph.get(i)){ System.out.println(i + " -> " + neighbor); } } System.out.println("Union Find"); UnionFind uf = new UnionFind(disJointGraph.size()); for(int i = 0; i < disJointGraph.size(); i++){ for(int neighbor : disJointGraph.get(i)){ uf.union(i, neighbor); } } // Connecting to different component - uf.union(2, 4); for(int i = 0; i < disJointGraph.size(); i++){ System.out.println("Node " + i + " has parent: " + uf.find(i)); } Set uniqueParents = new HashSet<>(); for(int i = 0; i < disJointGraph.size(); i++){ uniqueParents.add(uf.find(i)); } System.out.println("Number of connected components: " + uniqueParents.size()); } }