#include <bits/stdc++.h>
using namespace std;
struct hash_pair {
  template <class T1, class T2>
  size_t operator()(const pair<T1, T2>& p) const {
    auto hash1 = hash<T1>{}(p.first);
    auto hash2 = hash<T2>{}(p.second);
    return hash1 ^ hash2;
  }
};
long long t;
long long m = 1e9 + 7;
long long arr[5005] = {1}, chk[5005];
vector<long long> v[5005];
map<pair<long long, long long>, long long> mp;
long long res = 1;
void dfs(long long a) {
  chk[a] = 1;
  for (long long i = 0; i < v[a].size(); i++) {
    long long b = v[a][i];
    if (chk[b] == 1) {
      long long d = mp[{a, b}];
      res = 2;
      arr[d] = 2;
    } else if (chk[b] == 2)
      continue;
    else
      dfs(b);
  }
  chk[a] = 2;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  ;
  long long a, b, c, d, e, f, g, i, j;
  cin >> a >> b;
  for (i = 1; i <= b; i++) arr[i] = 1;
  f = 0;
  for (i = 1; i <= b; i++) {
    cin >> c >> d;
    v[c].push_back(d);
    mp[{c, d}] = i;
  }
  for (i = 1; i <= a; i++) {
    if (chk[i] == 0) {
      dfs(i);
    }
  }
  cout << res << endl;
  for (i = 1; i <= b; i++) {
    if (i != 1) cout << ' ';
    cout << arr[i];
  }
  return 0;
}
