#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 6;
const long long M = 1e9 + 7;
vector<int> g[N];
int vis[N], flag, now;
void dfs_cycle(int node) {
  vis[node] = 1;
  for (int it : g[node]) {
    if (flag) return;
    if (vis[it] == 1) {
      flag = 1;
      return;
    } else if (vis[it] == 0)
      dfs_cycle(it);
  }
  vis[node] = 2;
}
int main() {
  int n, m;
  scanf("%d", &n);
  scanf("%d", &m);
  int arr[m][2];
  for (int i = 0; i < m; i++) {
    int x, y;
    scanf("%d", &x);
    scanf("%d", &y);
    g[x].push_back(y);
    arr[i][0] = x;
    arr[i][1] = y;
  }
  for (int i = 1; i <= n; i++) {
    if (!vis[i]) {
      dfs_cycle(i);
    }
  }
  if (flag == 0) {
    printf("%d\n", 1);
    for (int i = 0; i < m; i++) printf("1 ");
    return 0;
  }
  printf("%d\n", 2);
  for (int i = 0; i < m; i++) {
    if (arr[i][0] < arr[i][1])
      printf("1 ");
    else
      printf("2 ");
  }
}
