#include <bits/stdc++.h>
using namespace std;
long long gcd(long long a, long long b) { return b == 0 ? a : gcd(b, a % b); }
long long lcm(long long a, long long b) { return a * (b / gcd(a, b)); }
const int N = 5005;
vector<pair<long long, long long> > v[N];
long long vis[N];
long long color[N];
long long k;
void dfs(long long node) {
  vis[node] = 1;
  for (auto i : v[node]) {
    if (vis[i.first] == 1) {
      color[i.second] = 2;
      k = 2;
      continue;
    } else {
      color[i.second] = 1;
      if (!vis[i.first]) dfs(i.first);
    }
  }
  vis[node] = 2;
}
void solve() {
  long long n, m, x, y;
  cin >> n >> m;
  for (long long i = 1; i <= m; i++) {
    cin >> x >> y;
    v[x].push_back({y, i});
  }
  k = 1;
  for (long long i = 1; i <= n; i++)
    if (!vis[i]) dfs(i);
  cout << k << '\n';
  for (long long i = 1; i <= m; i++) cout << color[i] << " ";
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int TESTS = 1;
  while (TESTS--) {
    solve();
  }
  cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
  return 0;
}
