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

using namespace std;

const int NMAX = 8191;

vector<int> L[1 + NMAX];
vector<int> R[1 + NMAX];

int n, m;

bool vizL[1 + NMAX];

int cuplajL[1 + NMAX];
int cuplajR[1 + NMAX];

bool luatL[1 + NMAX];
bool luatR[1 + NMAX];

int sol[1 + NMAX];

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

    for (auto vecin: L[nod])
    {
        if (cuplajR[vecin] == 0)
        {
            cuplajL[nod] = vecin;
            cuplajR[vecin] = nod;

            return true;
        }
    }

    for (auto vecin : L[nod])
    {
        if (cuplaj(cuplajR[vecin]))
        {
            cuplajL[nod] = vecin;
            cuplajR[vecin] = nod;

            return true;
        }
    }

    return false;
}

void hopcroftKarp()
{
    bool ok = true;

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

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

void suport(int nod)
{
  for (int vecin : L[nod])
  {
    if (!luatR[vecin])
    {
      luatR[vecin] = true;
      luatL[cuplajR[vecin]] = false;
      suport(cuplajR[vecin]);
    }
  }
}

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

  for (int i = 1; i <= n; i++)
    if (!luatL[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;

        L[a].push_back(b);
        R[b].push_back(a);
    }

    hopcroftKarp();

    minimumVertexCover();

    int dim = 0;

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

    out << dim << '\n';

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

    return 0;
}