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.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.StringTokenizer;

public class EEdu37 {
	public static void main(String[] args) {
		FS scan = new FS(System.in);
		int N = scan.nextInt(),  M = scan.nextInt();
		ArrayList<Integer>[] adj = new ArrayList[N];
		for(int i=0;i<N;i++)adj[i] = new ArrayList<>();
		for(int i=0;i<M;i++) {
			int u = scan.nextInt()-1, v = scan.nextInt()-1;
			adj[u].add(v);
			adj[v].add(u);
		}
		DisjointSet ds = new DisjointSet(N);
		boolean[] seen = new boolean[N];
		
		if(N<=500) {
			boolean[][] mat = new boolean[N][N];
			
			for(int i=0;i<N;i++)Arrays.fill(mat[i], true);
			for(int i =0;i<N;i++)for(int j : adj[i])mat[i][j] = mat[j][i] =false;
			
			ArrayDeque<Integer> q = new ArrayDeque<>();
			ArrayList<Integer> sol = new ArrayList<>();
			for(int i=0;i<N;i++) {
				if(seen[i])continue;
				seen[i] = true;
				
				q.add(i);
				int sz = 0;
				while(!q.isEmpty()) {
					int x = q.poll();
					sz++;
					for(int j=0;j<N;j++) {
						if(mat[x][j] && !seen[j]) {
							seen[j] = true;
							q.add(j);
						}
					}
				}
				sol.add(sz);
				
				
			}
			Collections.sort(sol);
			PrintWriter out = new PrintWriter(System.out);
			out.println(sol.size());
			for(int i=0;i<sol.size();i++)out.print(sol.get(i)+" ");
			out.println();
			out.close();
			
			return;
		}
		
		
		boolean[] a = new boolean[N];
		
		int idx = -1, min = 1000000;
		for(int i=0;i<N;i++)if(adj[i].size()< min) { min = adj[i].size(); idx = i;}
		for(int start=idx;start<N+idx;start++) {
			int i = start%N;
			if(seen[i])continue;
			
			seen[i] = true;
			ArrayDeque<Integer> q = new ArrayDeque<>();
			q.add(i);
			while(!q.isEmpty()) {
				int x = q.poll();
				Arrays.fill(a, false);
				for(int j : adj[x]) {
					a[j] = true;
					if(seen[j])continue;
					seen[j] = true;
					q.add(j);
				}
				for(int j=0;j<N;j++) {
					if(!a[j]) {
						ds.union(x, j);
						seen[j] = true;
					}
				}
			}
			
		}
		HashMap<Integer, Integer> map = new HashMap<>();
		
		for(int i=0;i<N;i++) {
			if(!map.containsKey(ds.id[i]))map.put(ds.id[i], 1);
			else map.put(ds.id[i], map.get(ds.id[i])+1);
		}
		
		ArrayList<Integer> sol =  new ArrayList<>();
		for(int i : map.values())sol.add(i);
		
		Collections.sort(sol);
		PrintWriter out = new PrintWriter(System.out);
		out.println(sol.size());
		for(int i=0;i<sol.size();i++)out.print(sol.get(i)+" ");
		out.println();
		out.close();
	}
	private static class FS {
		BufferedReader br;
		StringTokenizer st;
		public FS(InputStream in) {
			br = new BufferedReader(new InputStreamReader(in));
		}
		String next(){
			while(st==null||!st.hasMoreElements()){
				try{st = new StringTokenizer(br.readLine());}
				catch(IOException e){e.printStackTrace();}
			}
			return st.nextToken();
		}
		int nextInt() {return Integer.parseInt(next());}
		long nextLong() {return Long.parseLong(next());}
		double nextDouble() { return Double.parseDouble(next());}
	}
	private static class DisjointSet {
		int[] id, sz;
		public DisjointSet(int N) {//N=Number of verts
			id = new int[N];
			sz = new int[N];
			for (int i=0;i<N;i++){sz[i]=1;id[i]=i;}
		}
		 
		private int root(int i){
			return id[i] = (i!=id[i])?root(id[i]):i;
		}
		public boolean find(int p, int q){
			return root(p)==root(q);
		}
		public void union(int p, int q){
			int i=root(p);
			int j=root(q);
			if (sz[i]<sz[j]){id[i]=j;sz[j]+=sz[i];}
			else 			{id[j]=i;sz[i]+=sz[j];};
		}
	}
}
