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.beans.IntrospectionException;
import java.io.*;
import java.util.*;
public class CcInCg{
    private static int N = 200001;
    private static HashMap<Integer,Integer>[] graph = new HashMap[N];
    private static TreeSet<Integer> vertices = new TreeSet<>();
    private static boolean[] visited = new boolean[N];
    private static int bfs(int u){
        int cnt = 1;
        visited[u] = true;
        vertices.remove(u);
        LinkedList<Integer> queue = new LinkedList<>();
        queue.addLast(u);
        while(!queue.isEmpty()){
            int currNode = queue.removeFirst();
            ArrayList<Integer> removeArr = new ArrayList<>();
            Iterator<Integer> itr = vertices.iterator();
            while(itr.hasNext()){
                int v = itr.next();
                if(!graph[currNode].containsKey(v)){
                    visited[v] = true;
                    queue.addLast(v);
                    removeArr.add(v);
                    cnt++;
                }
            }
            for(int i=0;i<removeArr.size();i++)
                vertices.remove(removeArr.get(i));
        }
        return cnt;
    }
    public static void main(String[] args){
        InputReader reader = new InputReader();
        PrintWriter writer = new PrintWriter(new BufferedOutputStream(System.out));
        // your program goes here
        int n = reader.nextInt();
        int m = reader.nextInt();
        for(int i=0;i<n;i++) {
            graph[i] = new HashMap<>();
            vertices.add(i);
        }
        for(int i=0;i<m;i++){
            int u = reader.nextInt();
            int v = reader.nextInt();
            graph[u-1].put(v-1,1);
            graph[v-1].put(u-1,1);
        }
        int numComponents = 0;
        ArrayList<Integer> componentSizes = new ArrayList<>();
        for(int i=0;i<n;i++){
            if(!visited[i]) {
                componentSizes.add(bfs(i));
                numComponents++;
            }
        }
        writer.println(numComponents);
        Collections.sort(componentSizes);
        for(int i=0;i<componentSizes.size();i++)
            writer.print(componentSizes.get(i)+" ");
        writer.println();
        writer.close();
    }
    static class InputReader{
        BufferedReader br;
        StringTokenizer tokenizer;

        InputReader(){
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        public String next(){
            while(tokenizer==null || !tokenizer.hasMoreElements()){
                try{
                    tokenizer = new StringTokenizer(br.readLine());
                }catch(IOException e){
                    e.printStackTrace();
                }
            }
            return tokenizer.nextToken();
        }

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

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

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

        public String nextLine(){
            String str = "";
            try{
                str = br.readLine();
            }catch(IOException e){
                e.printStackTrace();
            }
            return str;
        }
    }
}

