#include <bits/stdc++.h>
using namespace std;
long long int col[5010];
long long int res[5010];
map<pair<long long int, long long int>, long long int> mp;
vector<vector<long long int> > v(5010);
bool tr;
void dfs(long long int x) {
  col[x] = 1;
  for (int i = 0; i < v[x].size(); i++) {
    if (col[v[x][i]] == 0) {
      dfs(v[x][i]);
      res[mp[make_pair(x, v[x][i])]] = 1;
    } else if (col[v[x][i]] == 2) {
      res[mp[make_pair(x, v[x][i])]] = 1;
    } else {
      res[mp[make_pair(x, v[x][i])]] = 2;
      tr = true;
    }
  }
  col[x] = 2;
}
int main() {
  long long int n, m, x, y, i;
  tr = false;
  cin >> n >> m;
  for (i = 0; i < m; i++) {
    cin >> x >> y;
    v[x].push_back(y);
    mp[make_pair(x, y)] = i;
  }
  for (i = 1; i <= n; i++) {
    if (col[i] == 0) dfs(i);
  }
  cout << (tr ? 2 : 1) << endl;
  for (i = 0; i < m; i++) cout << res[i] << " ";
  cout << endl;
}
