Problem: You are given a directed graph with n vertices and m directed edges without self-loops or multiple edges.

Let's denote the k-coloring of a digraph as following: you color each edge in one of k colors. The k-coloring is good if and only if there no cycle formed by edges of same color.

Find a good k-coloring of given digraph with minimum possible k.

Input

The first line contains two integers n and m (2 ≤ n ≤ 5000, 1 ≤ m ≤ 5000) — the number of vertices and edges in the digraph, respectively.

Next m lines contain description of edges — one per line. Each edge is a pair of integers u and v (1 ≤ u, v ≤ n, u ≠ v) — there is directed edge from u to v in the graph.

It is guaranteed that each ordered pair (u, v) appears in the list of edges at most once.

Output

In the first line print single integer k — the number of used colors in a good k-coloring of given graph.

In the second line print m integers c_1, c_2, ..., c_m (1 ≤ c_i ≤ k), where c_i is a color of the i-th edge (in order as they are given in the input).

If there are multiple answers print any of them (you still have to minimize k).

Examples

Input


4 5
1 2
1 3
3 4
2 4
1 4


Output


1
1 1 1 1 1 


Input


3 3
1 2
2 3
3 1


Output


2
1 1 2 

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
const int N = 5010;
vector<int> gfo[N];
int vst[N];
int color[N][N];
void dfs(int u) {
  vst[u] = 1;
  for (int v : gfo[u]) {
    if (vst[v] == 0) {
      color[u][v] = 1;
      dfs(v);
    }
    if (vst[v] == 1) {
      color[u][v] = 2;
    }
    if (vst[v] == 2) {
      color[u][v] = 1;
    }
  }
  vst[u] = 2;
}
int main() {
  int n, m;
  cin >> n >> m;
  vector<pair<int, int> > vec;
  for (int i = int(0); i < int(m); ++i) {
    int u, v;
    cin >> u >> v;
    u--, v--;
    gfo[u].push_back(v);
    vec.push_back({u, v});
  }
  for (int u = int(0); u < int(n); ++u)
    if (vst[u] == 0) dfs(u);
  int mx = 0;
  for (int i = int(0); i < int(m); ++i) {
    mx = max(mx, color[vec[i].first][vec[i].second]);
  }
  cout << mx << endl;
  for (int i = int(0); i < int(m); ++i) {
    cout << color[vec[i].first][vec[i].second] << " ";
  }
  cout << endl;
  return 0;
}