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.*;
import java.io.IOException;
import java.io.InputStream;
import java.util.StringTokenizer;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
 
public class Main {
    public static double PI = Math.acos(-1.0);
    public static double eps = 1e-6;	
    static class InputReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;
        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }
        public String next() {
            while(tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }
        public int nextInt() {
            return Integer.parseInt(next());
        }
        public long nextLong() {
            return Long.parseLong(next());
        }
    }
    public static int maxn = (int) (2e5 + 5);
    
    public static class Edge {
        int nxt;
        int to;
        Edge(int _nxt, int _to) {
            nxt = _nxt;
            to = _to;
        }
    }

    public static Edge[] E = new Edge[maxn*2];
    public static int[] head =  new int[maxn];
    public static int[] lnxt =  new int[maxn];
    public static int[] llst =  new int[maxn];
    public static int fst;
    public static int Etot;
    public static int Ctot;
    public static int[] C = new int[maxn];
    public static int[] q = new int[maxn];
    public static int lf;
    public static int rt;
    public static boolean[] vis = new boolean[maxn];
    public static int[] cnt = new int[maxn];
    public static int[] col = new int[maxn];
    public static void addEdge(int u, int v) {
        E[Etot] = new Edge(head[u], v);
        head[u] = Etot++;
    }
    public static void bfs(int x, int n) {
    	lf = rt = 0;
    	q[rt++] = x;
    	col[Ctot] = 0;
    	vis[x] = true;
    	if(x == fst) {
			fst = lnxt[fst];
		} else {
			if(lnxt[x] != -1) llst[lnxt[x]] = llst[x];
			if(llst[x] != -1) lnxt[llst[x]] = lnxt[x];
		}
    	while(lf < rt) {
    		int now = q[lf++];
    		++col[Ctot];
    		for(int i = head[now]; i != -1; i = E[i].nxt) {
    			int to = E[i].to;
    			++cnt[to];
    		}
    		int id = fst;
    		while(id != -1) {
    			if(!vis[id] && cnt[id] == 0) {
    				vis[id] = true;
    				q[rt++] = id;
    				if(id == fst) {
    	    			fst = lnxt[fst];
    	    			if(fst != -1) llst[fst] = -1;
    	    		} else {
    	    			if(lnxt[id] != -1) llst[lnxt[id]] = llst[id];
    	    			if(llst[id] != -1) lnxt[llst[id]] = lnxt[id];
    	    		}
    			}
    			id = lnxt[id];
    		}
    		for(int i = head[now]; i != -1; i = E[i].nxt) {
    			int to = E[i].to;
    			--cnt[to];
    		}
    	}
    	++Ctot;
    }
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
        int n = in.nextInt();
        int m = in.nextInt()	;
        llst[1] = -1;
        lnxt[n] = -1;
        Etot = Ctot = lf = rt = 0;
        fst = 1;
        for(int i = 1; i <= n; ++i) {
            head[i] = -1;
            vis[i] = false;
            cnt[i] = 0;
            if(i > 1) llst[i] = i - 1;
            if(i < n) lnxt[i] = i + 1;
        }
        for(int i = 0; i < m; ++i) {
            int u = in.nextInt();
            int v = in.nextInt();
            addEdge(u, v);
            addEdge(v, u);
        }
        for(int i = 1; i <= n; ++i) {
        	if(vis[i]) continue;
        	bfs(i, n);
        }
        Arrays.sort(col, 0, Ctot);
        out.println(Ctot);
//        out.flush();
        for(int i = 0; i < Ctot; ++i) {
        	if(i > 0) out.print(" ");
//            out.flush();
        	out.print(col[i]);
//            out.flush();
        }
        out.println();
        out.flush();
        // Scanner in = new Scanner(System.in);
        // in.close();
    }
}
		  		 						  	  	  		   		 	