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.*;
import java.util.*;

public class E implements Runnable{
	public static void main (String[] args) {new Thread(null, new E(), "_cf", 1 << 28).start();}

	int n;
	ArrayList<Integer>[] adj;

	public void run() {
		FastScanner fs = new FastScanner();
		PrintWriter out = new PrintWriter(System.out);
		System.err.println("Go!");

		int n = fs.nextInt();
		int m = fs.nextInt();
		adj = new ArrayList[n];
		for(int i = 0; i < n; i++) {
			adj[i] = new ArrayList<>();
		}
		Node[] a = new Node[n];
		for(int i = 0; i < n; i++) a[i] = new Node(i);
		for(int i = 0; i < m; i++) {
			int u = fs.nextInt()-1;
			int v = fs.nextInt()-1;
			a[u].adj.add(a[v]);
			a[v].adj.add(a[u]);
		}

		if(m == 0) {
			System.out.println(1 + "\n" + n);
			return;
		}//!

		Arrays.sort(a, (b, c) -> Integer.compare(b.adj.size(), c.adj.size()));
		for(int i = 0; i < n; i++) {
			Collections.sort(a[i].adj);
		}
		DSU ds = new DSU(n);
		boolean[] vis = new boolean[n];
		for(int i = 0; i < n; i++) {
			if(vis[a[i].id]) continue;
			int ptr = 0, union = 0;
			vis[a[i].id] = true;
			while(union < n) {
				if(union == a[i].id) {
					union++;
					continue;
				}
				while(ptr < a[i].adj.size() && a[i].adj.get(ptr).id == union) {
					ptr++; union++;
				}
				if(union < n) {
					ds.union(a[i].id, union);
					vis[union++] = true;
				}
			}
		}

		int comp = 0;
		ArrayList<Integer> res = new ArrayList<>();
		for(int i = 0; i < n; i++)
			if(ds.par[i] == i) {
				comp++;
				res.add(ds.size[i]);
			}

		Collections.sort(res);
		out.println(comp);
		for(int i = 0; i < res.size(); i++) {
			if(i > 0) out.print(" ");
			out.print(res.get(i));
		}
		out.println();

		out.close();
	}

	class Node implements Comparable<Node> {
		int id;
		ArrayList<Node> adj;
		Node (int a) {
			id = a;
			adj = new ArrayList<>();
		}
		public int compareTo (Node o) {
			return Integer.compare(id, o.id);
		}
	}

	class DSU {
		int n;
		int[] par, rank, size;
		int comp;
		DSU(int a) {
			n = a;
			comp = n;
			size = new int[n]; Arrays.fill(size, 1);
			par = new int[n];
			rank = new int[n];
			for(int i = 0; i < n; i++) par[i] = i;
		}
		int find(int a) {
			if(par[a] == a) return a;
			return par[a] = find(par[a]);
		}
		boolean union(int x, int y) {
			int px = find(x), py = find(y);
			if(px == py) return false;
			if(rank[px] >= rank[py]) {
				if(rank[px] == rank[py]) rank[px]++;
				par[py] = px;
				size[px] += size[py];
			}
			else {
				par[px] = py;
				size[py] += size[px];
			}
			comp--;
			return true;
		}
	} 

	void sort (int[] a) {
		int n = a.length;
		for(int i = 0; i < 1000; i++) {
			Random r = new Random();
			int x = r.nextInt(n), y = r.nextInt(n);
			int temp = a[x];
			a[x] = a[y];
			a[y] = temp;
		}
		Arrays.sort(a);
	}

	class FastScanner {
		BufferedReader br;
		StringTokenizer st;
		public FastScanner() {
			try	{
				br = new BufferedReader(new InputStreamReader(System.in));
				//                br = new BufferedReader(new FileReader("testdata.out"));
				st = new StringTokenizer("");
			} catch (Exception e){e.printStackTrace();}
		}
		public String next() {
			if (st.hasMoreTokens())	return st.nextToken();
			try {st = new StringTokenizer(br.readLine());}
			catch (Exception e) {e.printStackTrace();}
			return st.nextToken();
		}
		public int nextInt() {return Integer.parseInt(next());}
		public long nextLong() {return Long.parseLong(next());}
		public double nextDouble() {return Double.parseDouble(next());}

		public String nextLine() {
			String line = "";
			try {line = br.readLine();}
			catch (Exception e) {e.printStackTrace();}
			return line;
		}
		public Integer[] nextIntegerArray(int n) {
			Integer[] a = new Integer[n];
			for(int i = 0; i < n; i++) a[i] = nextInt();
			return a;
		}
		public int[] nextIntArray(int n) {
			int[] a = new int[n];
			for(int i = 0; i < n; i++) a[i] = nextInt();
			return a;
		}
		public char[] nextCharArray() {return nextLine().toCharArray();}
	}

}