#include <bits/stdc++.h>
using namespace std;
int head[5010], to[5010 << 1], nxt[5010 << 1], tot, sum;
inline void add(int x, int y) {
  to[++tot] = y;
  nxt[tot] = head[x];
  head[x] = tot;
}
char *p1, *p2, buf[100000];
int rd() {
  int x = 0;
  char c =
      (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 100000, stdin), p1 == p2)
           ? EOF
           : *p1++);
  while (c < 48) {
    c = (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 100000, stdin), p1 == p2)
             ? EOF
             : *p1++);
  }
  while (c > 47) {
    x = (((x << 2) + x) << 1) + (c ^ 48),
    c = (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 100000, stdin), p1 == p2)
             ? EOF
             : *p1++);
  }
  return x;
}
bool v1[5010], v2[5010];
int ar[5010][5010], ans[5010];
void dfs(int p) {
  v1[p] = v2[p] = 1;
  for (int i = head[p]; i; i = nxt[i]) {
    if (!v2[to[i]]) {
      ans[ar[p][to[i]]] = 1;
      sum++;
    }
    if (!v1[to[i]]) {
      dfs(to[i]);
    }
  }
  v2[p] = false;
}
int main() {
  int n = rd(), m = rd();
  for (int i = 1; i <= m; i++) {
    int x = rd(), y = rd();
    ar[x][y] = i;
    add(x, y);
  }
  for (int i = 1; i <= n; i++) {
    if (!v1[i]) {
      dfs(i);
    }
  }
  if (sum == m) {
    puts("1");
  } else {
    puts("2");
  }
  for (int i = 1; i <= m; i++) {
    if (!ans[i]) {
      cout << "2 ";
    } else {
      cout << "1 ";
    }
  }
}
