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 

#include <bits/stdc++.h>
using namespace std;
template <typename T>
inline void read(T &x) {
  char c;
  bool nega = 0;
  while ((!isdigit(c = getchar())) && (c != '-'))
    ;
  if (c == '-') {
    nega = 1;
    c = getchar();
  }
  x = c - 48;
  while (isdigit(c = getchar())) x = x * 10 + c - 48;
  if (nega) x = -x;
}
template <typename T>
inline void writep(T x) {
  if (x > 9) writep(x / 10);
  putchar(x % 10 + 48);
}
template <typename T>
inline void write(T x) {
  if (x < 0) {
    putchar('-');
    x = -x;
  }
  writep(x);
}
template <typename T>
inline void writeln(T x) {
  write(x);
  putchar('\n');
}
vector<int> g[200001];
vector<int> h[200001];
bool done[200001];
int n, m;
int r[200001];
int root(int u) {
  if (r[u] < 0) return u;
  return r[u] = root(r[u]);
}
void uni(int u, int v) {
  u = root(u);
  v = root(v);
  if (u == v) return;
  h[u].push_back(v);
  h[v].push_back(u);
  r[u] += r[v];
  r[v] = u;
}
vector<int> good;
vector<int> boss;
set<int> s;
int dfstime[200001];
vector<int> ans;
int ntime;
bool dfs(int u, int a) {
  if (s.find(u) == s.end()) {
    uni(u, a);
    return 1;
  }
  dfstime[u] = ntime;
  for (int v : h[u])
    if (dfstime[v] != ntime)
      if (dfs(v, a)) return 1;
  return 0;
}
int main() {
  read(n);
  read(m);
  for (int i = (1); i <= (n); i++) {
    r[i] = -1;
    good.push_back(i);
  }
  {
    int u, v;
    for (int i = (1); i <= (m); i++) {
      read(u);
      read(v);
      g[u].push_back(v);
      g[v].push_back(u);
    }
  }
  sort(good.begin(), good.end(),
       [](int a, int b) { return (g[a].size()) < (g[b].size()); });
  boss.push_back(good[0]);
  done[good[0]] = 1;
  for (int v : g[boss.back()]) s.insert(v);
  for (int i = (1); i <= (n); i++)
    if (s.find(i) == s.end()) {
      uni(boss.back(), i);
      done[i] = 1;
    }
  for (int u : good) {
    if (done[u]) continue;
    s.clear();
    for (int v : g[u]) s.insert(v);
    for (int v : boss) {
      int a = root(v);
      if ((-r[a]) > ((int)g[u].size())) {
        uni(u, v);
        done[u] = 1;
      } else {
        ntime++;
        if (dfs(v, u)) done[u] = 1;
      }
    }
    if (!done[u]) {
      boss.push_back(u);
      for (int i = (1); i <= (n); i++)
        if (s.find(i) == s.end()) {
          uni(boss.back(), i);
        }
    }
  }
  s.clear();
  for (int i : boss)
    if (s.find(root(i)) == s.end()) {
      s.insert(root(i));
      ans.push_back(-r[root(i)]);
    }
  sort(ans.begin(), ans.end());
  writeln(ans.size());
  for (int x : ans) write(x), putchar(' ');
}
