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 CF {

    public static int n;
    public static int count;
    public static TreeSet<Integer> visited = new TreeSet<>();
    public static Set<Integer>[] NonAdjList = new HashSet[200000];

    public static void dfs(int u) {
        List<Integer> next = new ArrayList<>();
        if (NonAdjList[u]==null){
            next.addAll(visited);
            count+= visited.size();
            visited.clear();
        }else{
            for (Integer i : visited) {
                if (!NonAdjList[u].contains(i)){
                    next.add(i);
                    count++;
                }
            }
            visited.removeAll(next);
        }
        for (int i = 0; i < next.size(); i++) {
            dfs(next.get(i));
        }
    }

    public static void main(String[] args) throws IOException {
        //FastScanner in = new FastScanner(new FileInputStream(new File("input.txt")));
        //PrintWriter out = new PrintWriter(new File("output.txt"));
        FastScanner in = new FastScanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        n = in.nextInt();
        int m = in.nextInt();
        for (int i = 0; i < m; i++) {
            int x = in.nextInt() - 1;
            int y = in.nextInt() - 1;
            if (NonAdjList[x] == null) {
                NonAdjList[x] = new HashSet<>();
            }
            NonAdjList[x].add(y);
            if (NonAdjList[y] == null) {
                NonAdjList[y] = new HashSet<>();
            }
            NonAdjList[y].add(x);
        }
        for (int i = 0; i < n; i++) {
            visited.add(i);
        }
        List<Integer> longs = new ArrayList<>();
        while(!visited.isEmpty()){
            count = 0;
            dfs(visited.first());
            longs.add(count);
        }
        out.println(longs.size());
        Collections.sort(longs);
        longs.forEach((e) -> out.print(e + " "));
        out.println();
        out.close();
    }

    public static List<int[]> list = new LinkedList<>();

    public static void Permute(int[] input, int startindex) {
        int size = input.length;
        if (size == startindex + 1) {
            int[] tab = new int[size];
            for (int i = 0; i < tab.length; i++) {
                tab[i] = input[i];
            }
            list.add(tab);
        } else {
            for (int i = startindex; i < size; i++) {
                int temp = input[i];
                input[i] = input[startindex];
                input[startindex] = temp;
                Permute(input, startindex + 1);
                int temp2 = input[i];
                input[i] = input[startindex];
                input[startindex] = temp2;
            }
        }
    }

    public static int[] radixSort(int[] f) {
        return radixSort(f, f.length);
    }

    public static int[] radixSort(int[] f, int n) {
        int[] to = new int[n];
        {
            int[] b = new int[65537];
            for (int i = 0; i < n; i++) {
                b[1 + (f[i] & 0xffff)]++;
            }
            for (int i = 1; i <= 65536; i++) {
                b[i] += b[i - 1];
            }
            for (int i = 0; i < n; i++) {
                to[b[f[i] & 0xffff]++] = f[i];
            }
            int[] d = f;
            f = to;
            to = d;
        }
        {
            int[] b = new int[65537];
            for (int i = 0; i < n; i++) {
                b[1 + (f[i] >>> 16)]++;
            }
            for (int i = 1; i <= 65536; i++) {
                b[i] += b[i - 1];
            }
            for (int i = 0; i < n; i++) {
                to[b[f[i] >>> 16]++] = f[i];
            }
            int[] d = f;
            f = to;
            to = d;
        }
        return f;

    }

    private static class FastScanner {

        private final InputStream stream;
        private final byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

        public FastScanner(InputStream stream) {
            this.stream = stream;
        }

        int read() {
            if (numChars == -1) {
                throw new InputMismatchException();
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }

        boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        boolean isEndline(int c) {
            return c == '\n' || c == '\r' || c == -1;
        }

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

        public int[] nextArrayInt(int n) {
            int tab[] = new int[n];
            for (int i = 0; i < n; i++) {
                tab[i] = nextInt();
            }
            return tab;
        }

        public String[] nextArrayString(int n) {
            String tab[] = new String[n];
            for (int i = 0; i < n; i++) {
                tab[i] = next();
            }
            return tab;
        }

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

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

        public String next() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public String nextLine() {
            int c = read();
            while (isEndline(c)) {
                c = read();
            }
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(c);
                c = read();
            } while (!isEndline(c));
            return res.toString();
        }
    }
}
