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#include <fstream>
#include <vector>
#include <cstring>
using namespace std;
const int kMaxN = 8200;
ifstream fin("felinare.in");
ofstream fout("felinare.out");
int N, M, l[kMaxN], r[kMaxN], sol;
vector<int> G[kMaxN];
bool use[kMaxN], use_l[kMaxN], use_r[kMaxN];
void Read() {
fin >> N >> M;
while (M--) {
int x, y;
fin >> x >> y;
G[x].push_back(y);
}
}
inline void Connect(int a, int b) {
l[a] = b;
r[b] = a;
use_l[a] = true;
}
bool Link(int node) {
if (use[node])
return false;
use[node] = true;
for (int i : G[node])
if (!r[i]) {
Connect(node, i);
return true;
}
for (int i : G[node])
if (Link(r[i])) {
Connect(node, i);
return true;
}
return false;
}
void Match() {
bool ok = true;
while (ok) {
ok = false;
memset(use, 0, sizeof use);
for (int i = 1; i <= N; ++i)
if (!l[i])
ok |= Link(i);
}
for (int i = 1; i <= N; ++i)
if (l[i])
++sol;
}
void SupportLink(int node) {
for (int i : G[node])
if (!use_r[i]) {
use_l[r[i]] = false;
use_r[i] = true;
SupportLink(r[i]);
}
}
void Support() {
for (int i = 1; i <= N; ++i)
if (!use_l[i])
SupportLink(i);
}
void Print() {
fout << 2 * N - sol << "\n";
for (int i = 1; i <= N; ++i)
fout << (((1 ^ use_r[i]) << 1) + (1 ^ use_l[i])) << "\n";
}
int main() {
Read();
Match();
Support();
Print();
return 0;
}