#include <bits/stdc++.h>
using namespace std;
vector<long long> g[5011], w[5011];
long long ans[5011];
long long vis[5011];
long long cyc;
long long dfs(long long u, long long po) {
  vis[u] = 1;
  for (long long i = 0; i < g[u].size(); ++i) {
    long long v = g[u][i], wt = w[u][i];
    if (ans[wt] == 0) {
      ans[wt] = 3 - po;
      dfs(v, 3 - po);
    }
  }
  return 0;
}
long long in[5011], out[5011];
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  ;
  long long n, m, i;
  cin >> n >> m;
  vector<pair<long long, long long> > vp;
  for (i = 1; i <= m; ++i) {
    long long x, y;
    cin >> x >> y;
    g[x].push_back(y);
    in[y]++;
    vp.push_back({x, y});
  }
  queue<long long> q;
  for (i = 1; i <= n; ++i)
    if (in[i] == 0) q.push(i);
  cyc = 0;
  while (!q.empty()) {
    long long c = q.front();
    q.pop();
    ++cyc;
    for (auto v : g[c]) {
      in[v]--;
      if (in[v] == 0) q.push(v);
    }
  }
  if (cyc == n) {
    cout << "1\n";
    for (i = 1; i <= m; ++i) cout << 1 << " ";
    cout << "\n";
    return 0;
  }
  cout << "2\n";
  for (i = 1; i <= m; ++i)
    cout << 1 + (vp[i - 1].first < vp[i - 1].second) << " ";
  cout << "\n";
  return 0;
}
