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.util.StringTokenizer;
import java.util.*;

public class e {
	
	static boolean vis[];
	static HashSet<Integer> cur = new HashSet<Integer>();
	static int N;
	static Set<Integer> adj[];
	
	public static void main(String[] args) {
		FastScanner in = new FastScanner();
		N = in.nextInt();
		int m = in.nextInt();
		adj = new HashSet[N];
		for(int i = 0; i < N; i++) adj[i] = new HashSet<Integer>();
		
		vis = new boolean[N];
		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);
		}
		TreeSet<Integer> ts = new TreeSet<Integer>();
		for(int i = 0; i < N; i++) {
			if(vis[i])continue;
			cur.clear();
			dfs(i);
			ts.add(cur.size());
		}
		System.out.println(ts.size());
		for(int a : ts) System.out.print(a+" ");
		
		
	}
	
	static void dfs(int node) {
		vis[node]=true;
		cur.add(node);
		for(int i = 0; i < N; i++) {
			if(!adj[node].contains(i) && !vis[i]) {
				vis[i]=true;
				dfs(i);
			}
		}
		
	}
	
	static class tarjan
	{
	    private int V;   //Vertices
	    private int preCount;
	    private int[] low;
	    private boolean[] visited;      
	    private List<Integer>[] graph;	//EdgeList
	    private List<List<Integer>> sccComp;
	    private Stack<Integer> stack;
	    private int[] scc;
	    private int curSCC;
	    //Get SCC components of an edge list
	    public List<List<Integer>> getSCComponents(List<Integer>[] graph) 
	    {
	    	scc = new int[graph.length];
	    	curSCC = 0;
	        V = graph.length;
	        this.graph = graph;
	        low = new int[V];
	        visited = new boolean[V];
	        stack = new Stack<Integer>();
	        sccComp = new ArrayList<>();
	 
	        for (int v = 0; v < V; v++)
	              if (!visited[v])
	                dfs(v);
	 
	        return sccComp;
	    }
	    
	    public void dfs(int v) 
	    {
	        low[v] = preCount++;
	        visited[v] = true;
	        stack.push(v);
	        int min = low[v];
	        for (int w : graph[v]) {
	            if (!visited[w])
	                dfs(w);
	            if (low[w] < min) 
	                min = low[w];
	        }
	        if (min < low[v])  { 
	            low[v] = min; 
	            return; 
	        }        
	        List<Integer> component = new ArrayList<Integer>();
	        int w;
	        do{
	            w = stack.pop();
	            component.add(w);
	            low[w] = V;  
	            scc[w] = curSCC;
	        } while (w != v);
	        sccComp.add(component);
	        curSCC++;
	    }    
	}
	
	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();
		}
		
	}

}
