import java.io.FileReader; import java.io.IOException; import java.util.*; public class clique1 { public static int n; public static void main(String[] args) throws IOException { Scanner r = new Scanner(new FileReader(args[0])); n = r.nextInt(); int m = r.nextInt(); long start = System.nanoTime(); TreeMap> map = new TreeMap<>(); PriorityQueue pq = new PriorityQueue<>(); int[] degrees = new int[n+1]; Stack stack = new Stack<>(); for (int i = 0; i < n; i++) { map.put(i+1, new ArrayList<>()); } for (int i = 0; i < m; i++) { int node1 = r.nextInt(); int node2 = r.nextInt(); map.get(node1).add(node2); map.get(node2).add(node1); } for (int i = 1; i < n+1; i++) { pq.add(new Pair(i, map.get(i).size())); degrees[i] = map.get(i).size(); } while(!pq.isEmpty()) { Pair minDegreeNode = pq.poll(); if (degrees[minDegreeNode.node]!=minDegreeNode.degree) continue; for (int connectedNode : map.get(minDegreeNode.node)) { if (degrees[connectedNode]!=0) { degrees[connectedNode] -= 1; pq.add(new Pair(connectedNode, degrees[connectedNode])); } } degrees[minDegreeNode.node] = 0; stack.add(minDegreeNode); } DSU dsu = new DSU(); int sMax = 0; int uStar = 0; boolean[] readded = new boolean[n+1]; while (!stack.isEmpty()) { Pair minDegreeNode = stack.pop(); for (int connectedNode : map.get(minDegreeNode.node)) { if (readded[connectedNode]) { int s = dsu.union(minDegreeNode.node, connectedNode); if (s!=0) { int newScore = s*minDegreeNode.degree; if (newScore>sMax) { sMax = newScore; uStar = dsu.find(minDegreeNode.node); } } } } readded[minDegreeNode.node] = true; } System.out.println(sMax + ", " + uStar); long end = System.nanoTime(); double elapsedMs = (end - start) / 1_000_000.0; System.out.printf("Runtime: %.3f ms%n", elapsedMs); } static class DSU { public int[] parents = new int[n+1]; public int[] size = new int[n+1]; public DSU() { for (int i = 1; i < n+1; i++) { size[i] = 1; parents[i] = i; } } public int find(int x) { if (parents[x] !=x) { parents[x] = find(parents[x]); } return parents[x]; } public int union(int n1, int n2) { int pn1 = find(n1); int pn2 = find(n2); if (pn1 == pn2) return 0; if (size[pn1] < size[pn2]) { int temp = pn1; pn1 = pn2; pn2 = temp; } parents[pn2] = pn1; size[pn1] += size[pn2]; return size[pn1]; } } static class Pair implements Comparable { public int node; public int degree; public Pair(int node, int degree) { this.node = node; this.degree = degree; } public int compareTo(Pair o) { if (this.degree == o.degree) { return Integer.compare(this.node, o.node); } return Integer.compare(this.degree, o.degree); } @Override public boolean equals(Object o) { if (this == o) return true; if (o == null || getClass() != o.getClass()) return false; Pair pair = (Pair) o; return node == pair.node && degree == pair.degree; } @Override public int hashCode() { return Objects.hash(node, degree); } } }