#include <fstream>
#include <vector>
#include <cstring>

using namespace std;

const int NMAX = 8191;

vector<int> st[1 + NMAX];
vector<int> dr[1 + NMAX];

int n, m;

bool vizSt[1 + NMAX];

int cuplajSt[1 + NMAX];
int cuplajDr[1 + NMAX];

bool luatSt[1 + NMAX];
bool luatDr[1 + NMAX];

int sol[1 + NMAX];

bool cuplaj(int nod)
{
    if (vizSt[nod])
        return false;
    vizSt[nod] = true;

    for (auto vecin: st[nod])
    {
        if (cuplajDr[vecin] == 0)
        {
            cuplajSt[nod] = vecin;
            cuplajDr[vecin] = nod;

            return true;
        }
    }

    for (auto vecin : st[nod])
    {
        if (cuplaj(cuplajDr[vecin]))
        {
            cuplajSt[nod] = vecin;
            cuplajDr[vecin] = nod;

            return true;
        }
    }

    return false;
}

void hopcroftKarp()
{
    bool ok = true;

    while (ok)
    {
        ok = false;
        memset(vizSt, 0, sizeof(vizSt));

        for (int i = 1; i <= n; i++)
            if (cuplajSt[i] == 0)
                ok |= cuplaj(i);
    }
}

void suport(int nod)
{
  for (int vecin : st[nod])
  {
    if (!luatDr[vecin])
    {
      luatDr[vecin] = true;
      luatSt[cuplajDr[vecin]] = false;
      suport(cuplajDr[vecin]);
    }
  }
}

void minimumVertexCover()
{
  for (int i = 1; i <= n; i++)
    if (cuplajSt[i] != 0)
      luatSt[i] = true;

  for (int i = 1; i <= n; i++)
    if (!luatSt[i])
      suport(i);
}

int main()
{
    ifstream in("felinare.in");
    ofstream out("felinare.out");

    in >> n >> m;

    for (int i = 1; i <= m; i++)
    {
        int a, b;
        in >> a >> b;

        st[a].push_back(b);
        dr[b].push_back(a);
    }

    hopcroftKarp();

    minimumVertexCover();

    int dim = 0;

    for (int i = 1; i <= n; i++)
    {
        if (!luatSt[i])
        {
            dim++;
            sol[i] |= 1;
        }
        if (!luatDr[i])
        {
            dim++;
            sol[i] |= 2;
        }
    }

    out << dim << '\n';

    for (int i = 1; i <= n; i++)
        out << sol[i] << '\n';

    return 0;
}