#include <bits/stdc++.h>
using namespace std;
const int maxn = 5000 + 5;
const int maxm = 100 + 5;
const int inf = 0x3f3f3f3f;
const long long mod = 1e9 + 7;
const double pi = acos(-1.0);
int n, m, u, v, flag;
int deg[maxn], col[maxn];
vector<int> g[maxn];
int topo() {
  memset(deg, 0, sizeof deg);
  for (int i = 1; i <= n; i++)
    for (auto it : g[i]) deg[it]++;
  queue<int> q;
  int num = 0;
  for (int i = 1; i <= n; i++)
    if (!deg[i]) q.push(i);
  while (!q.empty()) {
    int u = q.front();
    q.pop();
    num++;
    for (auto it : g[u]) {
      if (--deg[it] == 0) q.push(it);
    }
  }
  return num != n;
}
int main() {
  scanf("%d %d", &n, &m);
  for (int i = 1; i <= m; i++) {
    scanf("%d %d", &u, &v);
    g[u].push_back(v);
    col[i] = 1;
    if (topo()) {
      flag = 1;
      g[u].pop_back();
      col[i] = 2;
    }
  }
  if (flag)
    puts("2");
  else
    puts("1");
  for (int i = 1; i <= m; i++) printf("%d ", col[i]);
  return 0;
}
