#include <bits/stdc++.h>
#define _GLIBCXX_DEBUG
using namespace std;
using ll = long long;
using vec = vector<ll>;
using vect = vector<double>;
using Graph = vector<vector<ll>>;
#define loop(i, n) for (ll i = 0; i < n; i++)
#define Loop(i, m, n) for (ll i = m; i < n; i++)
#define pool(i, n) for (ll i = n; i >= 0; i--)
#define Pool(i, m, n) for (ll i = n; i >= m; i--)
#define mod 1000000007ll
#define flagcount __builtin_popcount
#define flag(x) (1 << x)
#define flagadd(bit, x) bit |= flag(x)
#define flagpop(bit, x) bit &= ~flag(x)
#define flagon(bit, i) bit &flag(i)
#define flagoff(bit, i) !(bit & (1 << i))
#define all(v) v.begin(), v.end()
#define low2way(v, x) lower_bound(all(v), x)
#define high2way(v, x) upper_bound(all(v), x)
#define idx_lower(v, x) (distance(v.begin(), low2way(v, x)))  //配列vでx未満の要素数を返す
#define idx_upper(v, x) (distance(v.begin(), high2way(v, x))) //配列vでx以下の要素数を返す
#define idx_lower2(v, x) (v.size() - idx_lower(v, x))         //配列vでx以上の要素数を返す
#define idx_upper2(v, x) (v.size() - idx_upper(v, x))         //配列vでxより大きい要素の数を返す
#define putout(a) cout << a << endl
#define Gput(a, b) G[a].push_back(b)
#define Sum(v) accumulate(all(v), 0ll)
#define gcd(x, y) __gcd(x, y)
ll ctoi(char c)
{
    if (c >= '0' && c <= '9')
    {
        return c - '0';
    }
    return 0;
}
template <typename T>
T lcm(T x, T y)
{
    T z = gcd(x, y);
    return x * y / z;
}
template <typename T>
bool primejudge(T n)
{
    if (n < 2)
        return false;
    else if (n == 2)
        return true;
    else if (n % 2 == 0)
        return false;
    double sqrtn = sqrt(n);
    for (T i = 3; i < sqrtn + 1; i++)
    {
        if (n % i == 0)
        {
            return false;
        }
        i++;
    }
    return true;
}
//場合によって使い分ける
//const ll dx[4]={1,0,-1,0};
//const ll dy[4]={0,1,0,-1};
const ll dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
const ll dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};
//2次元配列の宣言
//vector<vector<ll>> field(h, vector<ll>(w));
vector<vector<ll>> G;
vector<bool> seen;
map<pair<ll, ll>, ll> edgecolor; //(i,j)間の色(但し、i<j)
void dfs(ll v, ll color, ll maxcolor)
{ //現在見ている頂点と前の辺の色
    ll count = 1;
    for (auto nv : G[v])
    {
        if (seen[nv])
            continue;
        seen[nv] = true;
        ll nc = color + count;
        if (nc % maxcolor == 0)
            nc = maxcolor;
        else
            nc %= maxcolor;
        count++;
        ll s = v, t = nv;
        if (s > t)
            swap(s, t);
        edgecolor[make_pair(s, t)] = nc;
        dfs(nv, nc, maxcolor);
    }
    return;
}
int main()
{
    cout << fixed << setprecision(30);
    ll n;
    cin >> n;
    G.resize(n);
    seen.resize(n, false);
    vec a(n - 1), b(n - 1);
    vector<ll> A(n - 1), B(n - 1);
    loop(i, n - 1)
    {
        ll a, b;
        cin >> a >> b;
        a--;
        b--;
        A[i] = a;
        B[i] = b;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    ll maxcolor = 0; //グラフの最大次数
    loop(i, n)
    {
        maxcolor = max(maxcolor, (ll)G[i].size());
    }
    dfs(0, 1, maxcolor);
    putout(maxcolor);
    loop(i, n - 1)
    {
        ll S = A[i], T = B[i];
        if (S > T)
            swap(S, T);
        putout(edgecolor[make_pair(S, T)]);
    }
    return 0;
}

Measured memory_bytes: 17280