7 20
4 6
6 7
4 5
1 2
2 4
1 7
3 5
2 1
6 2
6 1
7 3
3 2
3 6
3 1
3 4
2 5
1 6
7 4
6 3
7 5
 8 23
1 2
1 4
1 6
1 8
2 3
2 4
2 5
2 6
2 7
2 8
3 4
3 5
3 6
3 7
3 8
4 5
4 6
4 7
5 6
5 7
5 8
6 8
7 8
 4 4
2 1
3 1
1 4
3 2
 8 18
1 4
1 6
1 7
2 3
2 4
2 5
2 6
2 7
2 8
3 4
3 8
4 7
5 6
5 7
5 8
6 7
6 8
7 8
 10 34
7 10
2 3
2 4
2 5
9 10
2 7
2 8
2 10
4 5
4 6
4 7
4 8
4 9
6 7
6 8
6 9
6 10
1 2
1 3
1 5
8 9
1 6
1 7
1 8
1 9
1 10
3 4
3 5
3 6
3 8
3 10
5 6
5 9
5 10
 5 7
1 2
2 3
3 4
1 5
2 5
3 5
4 5
 2 0
 8 23
2 7
7 5
8 6
8 2
6 3
3 5
8 1
8 4
8 3
3 4
1 2
2 6
5 2
6 4
7 6
6 5
7 8
7 1
5 4
3 7
1 4
3 1
3 2
 2 1
1 2
 6 9
1 2
1 4
1 5
2 3
2 5
2 6
3 5
4 6
5 6
 12 56
9 5
2 6
9 8
5 4
1 11
1 6
4 1
1 10
10 3
8 4
5 1
9 1
5 10
2 7
11 5
6 11
5 8
7 6
3 2
12 7
8 6
12 3
1 2
8 1
2 11
10 12
4 6
5 12
2 4
10 2
7 3
12 11
7 10
7 1
9 2
11 9
9 10
8 7
11 3
7 9
5 7
4 12
3 5
12 2
4 10
9 12
5 2
9 4
11 8
8 2
3 6
4 11
8 10
6 10
3 9
3 4
 12 58
1 2
1 3
1 4
1 5
1 6
1 7
1 8
1 10
1 11
1 12
2 3
2 4
2 5
2 6
2 7
2 8
2 9
2 10
2 11
2 12
3 4
3 5
3 6
3 7
3 8
3 9
3 10
3 11
3 12
4 5
4 6
4 8
4 11
4 12
5 6
5 7
5 8
5 9
5 10
5 11
6 7
6 8
6 9
6 10
6 11
6 12
7 8
7 9
7 10
7 11
7 12
8 9
8 10
8 11
9 10
9 11
9 12
10 12
 4 3
2 1
3 1
4 2
 3 1
2 3
 6 10
1 2
1 3
1 4
1 6
2 3
2 4
2 5
3 5
3 6
4 6
 11 49
10 3
6 4
11 3
7 6
10 6
6 1
4 3
10 2
4 5
9 2
10 1
5 7
1 5
9 7
2 11
8 6
3 9
2 5
9 5
6 5
1 4
11 9
1 7
8 10
3 6
3 7
11 5
6 9
4 10
8 7
4 9
8 2
4 2
8 11
7 4
9 10
8 1
10 7
3 2
5 8
8 9
1 3
2 7
10 11
5 3
10 5
4 11
1 11
8 3
 5 4
1 4
2 3
4 3
4 2
 4 3
1 2
3 1
4 3
 4 3
1 3
1 4
2 3
 10 36
7 8
7 9
2 3
2 4
2 5
9 10
2 7
2 8
2 9
2 10
4 5
4 6
4 7
4 8
4 10
6 7
6 9
6 10
1 2
1 3
1 4
8 9
1 5
8 10
1 7
1 8
1 9
1 10
3 4
3 6
3 7
3 9
5 6
5 7
5 9
5 10
 8 15
2 1
4 5
2 4
3 4
2 5
3 5
2 6
3 6
5 6
4 6
2 7
3 8
2 8
3 7
6 7

3
1 2 4 
 3
1 2 5 
 2
1 3 
 1
8 
 1
10 
 2
1 4 
 1
2 
 3
1 3 4 
 2
1 1 
 1
6 
 3
1 4 7 
 4
1 1 1 9 
 1
4 
 1
3 
 1
6 
 5
1 1 1 2 6 
 1
5 
 1
4 
 1
4 
 2
2 8 
 1
8 

import java.util.Arrays;
import java.util.LinkedList;
import java.util.Scanner;

public class Solution {
	public static void main(String[] args) {
		solve();
	}
	
	public static void solve() {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		
		@SuppressWarnings("unchecked")
		LinkedList<Integer>[] G = new LinkedList[n+1];
		
		for (int i = 0; i <= n; i++) {
			G[i] = new LinkedList<Integer>();
		}
		
		for (int i = 0; i < m; i++) {
			int x = sc.nextInt();
			int y = sc.nextInt();
			
			G[x].add(y);
			G[y].add(x);
		}
		
		Vertex[] V = new Vertex[n+1];
        for (int v = 1; v <= n; v++) {
            V[v] = new Vertex(v, null, null);
        }
        
        VertexList list1 = new VertexList();
        for(int v = 1; v < G.length; v++) {
        	list1.add(V[v]);
        }
        
        VertexList list2 = new VertexList();
        
        int[] nodesCC = new int[n];
		int cc = 0;
		for (int v = 1; v <= n; v++) {
			if(!V[v].visited) {
				nodesCC[cc] = bfs(G, v, V, list1, list2);
				cc++;
			}
		}
		
		Arrays.sort(nodesCC);
		
		System.out.println(cc);
		for (int i = 0; i < nodesCC.length; i++) {
			if (nodesCC[i] > 0) {
				System.out.print(nodesCC[i] + " ");
			}
		}
		System.out.println();
		
		sc.close();
	}
	
	public static int bfs(LinkedList<Integer>[] G, int s, Vertex[] V, VertexList list1, VertexList list2) {
		list1.remove(V[s]);
        
        LinkedList<Integer> Q = new LinkedList<Integer>();
        Q.addLast(s);
        V[s].visited = true;
        int count = 1;
        while(!Q.isEmpty()) {
            int u = Q.removeFirst();
            
            for (int v : G[u]) {
                if (!V[v].visited) {
                    list1.remove(V[v]);
                    list2.add(V[v]);
                }
            }
            
            Vertex v = list1.first;
            while(v != null) {
                v.visited = true;
                Q.addLast(v.key);
                v = v.next;
                
                count++;
            }
            list1.first = list2.first;
            list1.last = list2.last;
            list2.clear();
        }
        
        return count;
	}
	
	static class VertexList {
        Vertex first, last;
        
        VertexList() {
            first = null;
            last = null;
        }
        
        void add(Vertex v) {
            if (first == null) {
                first = v;
                last = v;
            }
            
            else {
                last.next = v;
                v.prev = last;
                last = v;
            }
        }
        
        void remove(Vertex v) {
            if (v.prev == null) {
                first = v.next;
            } else {
                v.prev.next = v.next;
            }
            
            if (v.next == null) {
                last = v.prev;
            } else {
                v.next.prev = v.prev;
            }
            
            v.prev = null;
            v.next = null;
        }
        
        void clear() {
            first = null;
            last = null;
        }
    }
    
    static class Vertex {
        Vertex prev, next;
        int key;
        boolean visited;
        
        public Vertex(int key, Vertex prev, Vertex next) {
            this.key = key;
            this.prev = prev;
            this.next = next;
        }
    }
}