#include <iostream>
#include <string>
#include <algorithm>
#include <cstdlib>
#include <cmath>
#include <vector>
#include <list>
#include <cstdint>
#include <bits/stdc++.h>
#include <queue>
#include <set>

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep_r(i, n) for (int i = n - 1; i >= 0; i--)
#define rep1(i, n) for (int i = 1; i <= (int)(n); i++)
#define REP(i, n) for (int i = 0, i##_len = (n); i < i##_len; ++i)
#define all(x) (x).begin(), (x).end()
#define SZ(x) ((ll)(x).size())
#define bit(n) (1LL << (n))
#define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end());

#define INF bit(60)
#define pb push_back
#define mod 1000000007

template <class T>
bool chmax(T &a, const T &b)
{
  if (a < b)
  {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T &a, const T &b)
{
  if (b < a)
  {
    a = b;
    return 1;
  }
  return 0;
}

using namespace std;
using uif = uint_fast64_t;
using ll = long long int;

int qp(int a, ll b)
{
  int ans = 1;
  do
  {
    if (b & 1)
      ans = 1ll * ans * a % mod;
    a = 1ll * a * a % mod;
  } while (b >>= 1);
  return ans;
}
int qp(int a, ll b, int mo)
{
  int ans = 1;
  do
  {
    if (b & 1)
      ans = 1ll * ans * a % mo;
    a = 1ll * a * a % mo;
  } while (b >>= 1);
  return ans;
}

int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};

#define FACSIZE 2002

ll invfac[FACSIZE];
ll fac[FACSIZE];

ll mod_pow(ll, ll);
ll mod_add(ll, ll);
ll mod_mul(ll, ll);
ll mod_div(ll, ll);
void make_fact(ll);
void make_invfact(ll);

struct Node
{
  ll val;
  ll parent;
  unordered_set<Node *> child;
};

ll enc(ll a, ll b)
{
  return a * 200000LL + b;
}

int main(void)
{

  ll n;
  cin >> n;
  ll max_color = 0;
  unordered_map<ll, unordered_set<ll>> g;
  unordered_map<ll, ll> g_idx;
  vector<ll> ans(n - 1, 0);
  Node *root = new Node;
  root->val = 1;
  root->parent = 0;
  rep(i, n - 1)
  {
    ll a, b;
    cin >> a >> b;
    g[a].insert(b);
    g[b].insert(a);
    g_idx[enc(a, b)] = i;
  }
  queue<Node *> que;
  que.push(root);
  while (!que.empty())
  {
    auto q = que.front();
    que.pop();
    for (auto n : g[q->val])
    {
      if (n != q->parent)
      {
        auto node = new Node;
        node->val = n;
        node->parent = q->val;
        q->child.insert(node);
        que.push(node);
      }
    }
  }
  que.push(root);
  set<ll> edges;
  ll edge_cnt;
  stack<ll> p_edges;
  while (!que.empty())
  {
    auto q = que.front();
    que.pop();
    //cerr << q->val << endl;
    ll p_idx;
    if (q->val == 1)
    {
      p_idx = -1;
    }
    else
    {
      ll p = q->parent;
      ll c = q->val;
      if (g_idx.find(enc(p, c)) != end(g_idx))
        p_idx = g_idx[enc(p, c)];
      else
        p_idx = g_idx[enc(c, p)];
    }
    if (p_idx == -1)
    {
      edge_cnt = 1;
    }
    else
    {
      if (ans[p_idx] == 1)
      {
        edge_cnt = 2;
      }
      else
        edge_cnt = 1;
    }
    for (auto n : q->child)
    {
      //cerr << "child:" << n->val << " ";
      ll idx;
      ll p = q->val;
      ll c = n->val;
      if (g_idx.find(enc(p, c)) != end(g_idx))
        idx = g_idx[enc(p, c)];
      else
        idx = g_idx[enc(c, p)];
      ans[idx] = edge_cnt;
      chmax(max_color, edge_cnt);
      if (ans[p_idx] == (++edge_cnt))
        edge_cnt++;

      que.push(n);
    }
    //cerr << endl;
  }
  cout << max_color << endl;
  for (auto x : ans)
  {
    cout << x << endl;
  }

  return 0;
}

ll mod_pow(ll x, ll r)
{
  if (r == 0)
    return 1;
  else if (r == 1)
    return x % mod;
  else if (r % 2 == 0)
  {
    ll t = mod_pow(x, r / 2) % mod;
    return t * t % mod;
  }
  else
  {
    ll t = mod_pow(x, r / 2) % mod;
    ll k = t * t % mod;
    return k * x % mod;
  }
}
ll mod_add(ll a, ll b)
{
  return (a + b) % mod;
}

ll mod_mul(ll a, ll b)
{
  return (a * b) % mod;
}

ll mod_div(ll a, ll b)
{
  return mod_mul(a, mod_pow(b, mod - 2));
}

void make_fact(ll n)
{
  fac[0] = 1;
  rep(i, n)
  {
    fac[i + 1] = mod_mul(fac[i], i + 1);
  }
}

void make_invfact(ll n)
{
  invfac[n] = mod_pow(fac[n], mod - 2);
  for (int i = n - 1; i >= 0; i--)
  {
    invfac[i] = mod_mul(invfac[i + 1], i + 1);
  }
}

Measured memory_bytes: 37704