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.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;
import java.util.*;

public class e2 {
	

	static HashSet<Integer> cur = new HashSet<Integer>();
	static int N;
	static Set<Integer> adj[];
	
	public static void main(String[] args) {
		FastScanner in = new FastScanner();
		PrintWriter out = new PrintWriter(System.out);
		N = in.nextInt();
		int m = in.nextInt();
		adj = new HashSet[N];
		for(int i = 0; i < N; i++) adj[i] = new HashSet<Integer>();
	
		for(int i = 0; i < m; i++) {
			int v1 = in.nextInt()-1;
			int v2 = in.nextInt()-1;
			adj[v1].add(v2);
			adj[v2].add(v1);
		}
		
		DisjointSet dsu = new DisjointSet(N);
		boolean vis[] = new boolean[N];
		for(int i = 0; i < N; i++) {
			if(vis[i])continue;
			//if(vis[dsu.find(i)])continue;
			vis[i] = true;
			//vis[dsu.find(i)]=true;
			
			for(int j = 0; j < N; j++) {
				if(!adj[i].contains(j)) {
					vis[j]=true;
					dsu.union(i,j);
				}
			}
		}
		HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();
		for(int i = 0; i < N; i++) {
			map.put(dsu.find(i), 1+map.getOrDefault(dsu.find(i), 0));
		}
		ArrayList<Integer> nums = new ArrayList<Integer>();
		for(int i = 0; i < N; i++) {
			if(map.containsKey(i)) {
				nums.add(map.get(i));
			}
		}
		Collections.sort(nums);
		out.println(nums.size());
		for(int i = 0; i < nums.size(); i++) out.print(nums.get(i)+" ");
		out.close();
	}
	
	static class DisjointSet {
		int[] s;
		
		public DisjointSet(int n) {
			Arrays.fill(s = new int[n], -1);
		}
		
		public int find(int i) {
			return s[i] < 0 ? i : (s[i] = find(s[i]));
		}
		
		public boolean union(int a, int b) {
			if ((a = find(a)) == (b = find(b))) return false;
			if(s[a] == s[b]) s[a]--;
			if(s[a] <= s[b]) s[b] = a; else s[a] = b;
			return true;
		}
	}
	
	static class FastScanner{
		BufferedReader br;
		StringTokenizer st;
		public FastScanner(String s) {
			try{
				br = new BufferedReader(new FileReader(s));
			}
			catch(FileNotFoundException e) {
				e.printStackTrace();
			}
		}
		public FastScanner(){
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		
		String nextToken()	{
			while(st == null ||!st.hasMoreElements()){
				try {
				st = new StringTokenizer(br.readLine());}
				catch(IOException e) {
					e.printStackTrace();
				}			
			}
			return st.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(nextToken());
		}
		long nextLong() {
			return Long.parseLong(nextToken());
		}
		double nextDouble() {
			return Double.parseDouble(nextToken());
		}
		String next() {
			return nextToken();
		}
		
	}

}
