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.*;
import java.math.*;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
public class Main {
  static Set<Integer> a[] = new Set[250005];
  static BitSet vis = new BitSet(250005);
 // static Set<Integer> a[] = new Set[10];
 // static BitSet vis = new BitSet(10);
  
  static ArrayList<Integer> ans;
  static int n = 0;

  static int dfs(int v)
  {
    int ans = 1;
    vis.clear(v);
    for (int i = vis.nextSetBit(1);i >= 1 && i <= n;i = vis.nextSetBit(i + 1)) {
      if (!a[v].contains(i)) {
        ans += dfs(i);
        //System.out.println("i:"+i + " ans:"+ans);
      }
    }
    return ans;
    
    
    
  }


  
  public static void main(String[] args) {
    try {
      MScanner in = new MScanner(System.in);
      BufferedWriter out = new BufferedWriter(new OutputStreamWriter(System.out, "UTF-8"));

      n = in.nextInt();
      int m = in.nextInt();
      
      for (int i = 0;i <= n;++i) {
        a[i] = new TreeSet<Integer>();
      }
      for (int i = 0;i < m;++i) {
        int i1 = in.nextInt();
        int i2 = in.nextInt();
        a[i1].add(i2);
        a[i2].add(i1);
      }
      for (int i = 1;i <= n;++i) {
        vis.set(i);
      }
      
      ArrayList<Integer> ans = new ArrayList<>();
      for (int i = 1;i <= n;++i) {
        if (vis.get(i)) {
          int sz = dfs(i);
          ans.add(sz);
        }
      }
      Collections.sort(ans);
      System.out.println(ans.size());
      for (int i = 0;i < ans.size();++i) {
        System.out.print(ans.get(i) + " ");
      }
      System.out.println();
        
      
      

    } catch (Exception e) {
      e.printStackTrace();
    }
  }
  static class MScanner {
    StringTokenizer st;
    BufferedReader br;
    public MScanner(InputStream system) {
      br = new BufferedReader(new InputStreamReader(system));
    }

    public MScanner(String file) throws Exception {
      br = new BufferedReader(new FileReader(file));
    }

    public String next() throws IOException {
      while (st == null || !st.hasMoreTokens())
        st = new StringTokenizer(br.readLine());
      return st.nextToken();
    }
    public int[] takearr(int n) throws IOException {
      int[]in=new int[n];for(int i=0;i<n;i++)in[i]=nextInt();
      return in;
    }
    public long[] takearrl(int n) throws IOException {
      long[]in=new long[n];for(int i=0;i<n;i++)in[i]=nextLong();
      return in;
    }
    public Integer[] takearrobj(int n) throws IOException {
      Integer[]in=new Integer[n];for(int i=0;i<n;i++)in[i]=nextInt();
      return in;
    }
    public Long[] takearrlobj(int n) throws IOException {
      Long[]in=new Long[n];for(int i=0;i<n;i++)in[i]=nextLong();
      return in;
    }
    public String nextLine() throws IOException {
      return br.readLine();
    }

    public int nextInt() throws IOException {
      return Integer.parseInt(next());
    }

    public double nextDouble() throws IOException {
      return Double.parseDouble(next());
    }

    public char nextChar() throws IOException {
      return next().charAt(0);
    }

    public Long nextLong() throws IOException {
      return Long.parseLong(next());
    }

    public boolean ready() throws IOException {
      return br.ready();
    }

    public void waitForInput() throws InterruptedException {
      Thread.sleep(3000);
    }
  }
}
